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Introduction to Physics Teacher ResourcePack
The Physics TRP is intended to support teacherspreparing students for the Physics component ofOCR Co-ordinated Science A or OCR Chemistry. Itis supported by a CD-ROM where much of thematerial in the Physics TRP is available in a formthat can easily be adapted to meet the needs ofindividual or groups of students.
The main features in the Physics TRP are.
Time allocation
The OCR specification splits up the content intoTeaching blocks. These Teaching blocks are not allof equal length. The Time Allocation page gives anestimation of how much time should be spent oneach Teaching block. It is an estimate made by thepeople who wrote the OCR specification andshould be a useful guide to teachers.
Activities
There are 25 Practical Activities suitable forstudents. Most of them are intended to help you todevelop Sc1 skills in your students beforeAssessment. Some of these activities can lead toSc1 assessments. There is one activity onProjectiles where full marking criteria are given.Providing they are used correctly they should assistCentres in their Sc1 assessment.
From 2003, computer based activities can be usedin addition to the traditional activities. There isone example of a suitable computer-based activity.Several of the activities give ideas of how ICT canbe used in student Practical Activities. There arealso examples of activities that can involveLiteracy and ICT.
These Activities are all arranged in the order thatthey appear in the textbook.
Learning support
Although Heinemann/OCR textbooks are writtenfor a wide ability range, we are conscious that it isimportant to tailor materials for lower abilitystudents. Topic help is intended to do this and, viathe CD-ROM, have the maximum flexibility. It isbased upon using the Key words identified in thetextbooks. Many candidates fail to understandscientific terminology and use it incorrectly.
Self-assessment (Quizzes)
The Heinemann/OCR textbooks and Homeworkbooks provide a whole range of questions. OCR areproviding End-of-unit tests that can be used tomonitor the progress of students. Self-assessment isnon-threatening and students can use it themselveswhen there is a suitable time, e.g. before taking anEnd-of-block test or when a piece of practical work
is finished. Self-assessment is provided at bothFoundation and Higher levels. Using thisSelf-assessment may highlight weaknesses to thestudent.
Summary sheets for KS3
In GCSE examinations, even at Foundation tier,examiners cannot examine KS3 material. Teachersmust therefore move on as quickly as possible toKS4. However, understanding of KS4 often requiresremembering what was done at KS3. At the start ofeach Teaching block there is a Check-up forstudents. This could be done by students on a pieceof paper and followed up by discussion or could bedone with the class on a discussion basis. If some,or all students have weaknesses, they can be givena Summary sheet.
Student Checklists
The Student sheets expand the OCR specificationand simplify the language for students. Studentscould be given a copy of the Student sheet at thestart of the Teaching block. They then tick off thestatements as they cover them in column A. Whenthey are confident that they can answers questionson the statement they tick column B. This thenprovides the basis for their revision planning, firstfor the End-of-block test and then for the Terminalexamination. It is hoped that using these will helpstudents organise really good individual revisionplans.
Help with Key skills
The Physics TRP gives advice for teachers onwhere and how to collect evidence for Key skills.There are tables that can be completed to keep arecord of Key skills opportunities.
Scheme of Work
To assist schools in producing individualisedschemes of work based on OCR A, tables are givenwhich summarise activities provided in PhysicsTRP and further activities that could be used.
Answers to questions
The Physics TRP includes answers to all of thequestions in Physics double and separate Physicsbooks. Teachers can use these to mark answers orcopy the relevant parts and give to students. Thiscan be useful if students have missed work becauseof absence.
It is hoped that the material provided by thePhysics TRP both in paper form and on PhysicsCD-ROM, will supplement material provided byOCR, and give a level of support much greater thanhas ever existed before.
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Contents
Schemes of work vi–x
Introduction to Key skills xi–xvii
Time allocation xviii
Activities (numbers relate to book spreads)
1.1 Resistors connected in series 1
1.3A Current–voltage graph for a metallicconductor 2
1.3B Current–voltage graph for the filamentof a light bulb 3
2.1 Balancing metre rules 4
2.2 How speed affects stopping distance 6
2.5 Friction 7
2.7 To investigate a factor which affects thedistance travelled by a projectile 8
2.9 Measuring reaction time 9
2.10A Dropping steel ball bearings in oil 11
2.10B Velocity–time graphs for falling balls 12
2.11 What difference does a lid make? 13
3.4 Reflection of light by a plane mirror 14
3.5A Refraction of light by a perspex block 15
3.5B (and A2.1)
How does the angle change? 16
4.1 The visible spectrum 17
4.6–4.8 Where do the earthquakes happen? 18
5.2 Absorption of radioactivity: Teacherdemonstration 19
5.3 Simulation of radioactive decay 20
7.3 Use of a van de Graaff generator to linkelectric charge and current:Teacher demonstration 21
8.2 How fast does the motor go? 22
8.3 How does voltage depend on speed? 23
8.4 Electromagnetic induction 24
8.5 Transforming the voltage 25
8.6 Literacy activity 27
A1.1–A1.3 or A1.4 for High Tier pupilsLogic Circuits using AND, OR andNOT gates 28
A3.6 Measuring specific heat capacity 30
A3.7 Efficiency of a ramp 31
Teachers’ and Technicians’ notes 32–65
Topic Help
Introduction 66
TB1 Electric circuits 67
TB2 Forces and energy 70
TB3 Wave properties 80
TB4 Using waves 85
TB5 Radioactivity 92
TB6 The Earth and Universe 97
TB7 Using electricity 100
TB8 Electromagnetism 105
Answers 111–118
Self-assessment
TB1 Electric circuits 119
TB2 Forces and energy 123
TB3 Wave properties 127
TB4 Using waves 131
TB5 Radioactivity 135
TB6 The Earth and Universe 139
TB7 Using electricity 143
TB8 Electromagnetism 147
TBA1 Electronics and control 151
TBA2 Processing waves 153
TBA3 More about forces and energy 155
Summary sheets
TB1 Electric circuits 157
TB2 Forces and energy 158
TB3 Wave properties 160
TB4 Using waves 161
TB5 Radioactivity 162
TB6 The Earth and Universe 163
TB7 Using electricity 164
TB8 Electromagnetism 165
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Student checklists
TB1 Electric circuits 166
TB2 Forces and energy 167
TB3 Wave properties 169
TB4 Using waves 171
TB5 Radioactivity 173
TB6 The Earth and Universe 174
TB7 Using electricity 175
TB8 Electromagnetism 177
TBA1 Electronics and control 178
TBA2 Processing waves 179
TBA3 More about forces and energy 181
Answers to pupil book questions 183–238
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vi Exp – Experiment; ICT – Activity suitable for assessing Sc1; Lit – Literacy Activity
Pupil book spread Activities in Physics TRP Further workElectric Circuits
1.1 Circuit components E. Resistors connected in series. E Using a variable resistor with lamp and/or motor
1.2 Measuring resistance E. Measure current and voltage in series and parallel
E. Measuring resistance
1.3 More about resistance E. Current–voltage graph for a metallic conductor
E Current–voltage graph for the filament of a lightbulb
CD-ROMs to enable pupils to construct, test and alter electric circuits on screen are: Crocodile Clips(www.crocodile-clips.com/education) and Edison (REM Ltd, Great Western House, Langport, Somerset,TA10 9YU)
Forces and energy
2.1 Turning forces E-Balancing metre rules Calculations involving moments
2.2 Motion graphs E. How speed affects stopping distance E-Comparing the advantages and disadvantages of using a stopclock, ticker tape and light gates to calculateaverage speed
How speed cameras work
2.3 Displacement and velocity E. Use a datalogger to measure distance, displacement and speed (and to graph the results)
2.4 Acceleration E Use a datalogger to measure acceleration
E use a datalogger to measure velocity–time graphs
2.5 Forces E. Friction
2.6 Force and motion E. Forces acting on objects in various situations and link to motion
CD-ROM Multimedia Motion- show and analyse different types of motion. Cambridge Science Media, 354Mill Road, Cambridge CB1 3NN
2.7 Force and acceleration Sc1- To investigate a factor which affects the distancetravelled by a projectile
E. Verify F = ma using ticker tape and light gates with a ticker timer
2.8 Force and energy E. Measuring personal power
2.9 On the road E Measuring reaction time Literacy – Discussion of the effects of increasing size of lorries on our roads
2.10 How things fall E. Dropping steel ball bearings in oil
E. Velocity – time graphs for falling balls
2.11 Keeping warm ICT–What difference does a lid make? E. Compare the conductivity of various materials
ICT – Internet research on U values for different materials
2.12 Energy efficiency E. Efficiency of simple machines (ramp and pulleysystems)
ICT – Internet research on combined heat and power systems
Wave properties
3.1 What are waves? E. Looking at waves with slinky springs, tuning forks and musical instruments
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Pupil book spread Activities in Physics TRP Further work3.2 Wave characteristics E. Examine waves in vibrating springs to show amplitude, frequency and wavelength
3.3 Water waves E. Use ripple tank and curved waves at straight and curved barriers
3.4 Reflection of light and sound E. Reflection of light by a plane mirror. ICT – Research on acoustic baffles and sound absorption materials
3.5 Refraction E. Refraction of light by a perspex block
ICT – How does the angle change?
3.6 Images E. Image positioning by no-parallax for both reflection and refraction
E. Counting images in inclined mirrors
Making kaleidoscope
3.7 Diffraction E. Use a ripple tank to demonstrate diffraction
Using waves
4.1 The electromagnetic spectrum E. The visible spectrum and show ir beyond red withir detector.
E. Showing ir beyond red with ir detector
ICT – Internet research on Newton
4.2 Infrared and ultraviolet
4.3 Opposite ends ICT – Research satellite dishes, e.g. www.goonhilly.bt.com
Location of mobile phone masts
4.4 Total internal reflection E. Demonstration of use of optic fibres
ICT – Research endoscope images on Internet
4.5 Ultrasound ICT – Research on uses of ultrasonics on Internet
4.6 Seismic waves ICT – Where do the earthquakes happen? (Also 4.7and 4.8)
E – Showing vibrations travel through the Earth
Interpreting traces of seismic waves
4.7 The structure of the Earth
4.8 Plate tectonics ICT – Research on the Internet of the work of Wegener
Study of the effects of recent earthquakes
(Possible links with Geography department throughout)
Radioactivity
5.1 What is radioactivity? E. Demonstrate background radioactivity
Leaflets on radiation and its effects from Press and Information Officer, National Radiological ProtectionBoard, Chilton, Didcot, Oxon OX11 0RQ
SATIS (Science and Technology in Society) – published by ASE – 204 Using radioactivity, 1105 Radon inhomes
Sang, David 1997 Henri Becquerel and the Discovery of Radioactivity (ASE publications)
Research on Becquerel on the Internet
Ellis, P1999 100 years of Radium (ASE publications) – the work of Pierre and Marie Curie
5.2 Properties of radiation E. Absorption of radioactivity: Teacherdemonstration
E. Demonstrate ionisation of air using spark counter Structure of film badge – also NRPB
5.3 Radioactive decay ICT – Simulation of radioactive decay
5.4 Using penetrative power of radioactivity E. Demonstrate smoke alarm
5.5 Other uses of radioactivity ICT – Research on Turin shroud, Iceman and radiocarbon dating
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viii Pupil book spread Activities in Physics TRP Further work5.6 Using radioactivity safely
The Earth and Universe
6.1 Our Solar System ICT – Internet research with NASA sites(www.nasa.gov)
CD-ROM – Astronomy, Anglia Multimedia, Rouen House, Rouen Road, Norwich, NR1 1RB
Posters, slides, videos, CD-ROMs available from Public Understanding of Science, Particle Physics andAstronomy Research Council, Polaris House, North Star Avenue, Swindon, Wiltshire, SN2 1ZZ
6.2 The life cycle of stars Slide set Stars and Galaxies II (available from Armagh Planetarium)
(www.armagh-planetarium.co.uk/index.htm)
Shows photographs of a star that blew up. Source of other useful materials
6.3 The evolution of the Universe
Using electricity
7.1 Electrostatic phenomena E. Using polythene and perspex rods for electrostatics
7.2 Uses and problems of electrostatics
7.3 Charge and current E. Use of a Van de Graaf generator to link electriccharge and current: Teacher demonstration
E. Demonstrate ping-pong ball between charged plates
7.4 Electricity in the home E. Measure energy transferred by different appliances (using a.c. ammeter or power using a joulemeter)
7.5 Electrical safety Resources available from local electricity company
7.6 Paying for electricity Wattville is a CD-ROM available from Understanding Electricity. It looks at electricity consumption in thehome
Electromagnetism
8.1 Force on a wire in a magnetic field E. Demonstration of ‘kicking wire’ experiment
Construction of a loudspeaker
8.2 Electric motors ICT – How fast does the motor go? E. Making a model motor
8.3 Electromagnetic induction ICT – How does voltage depend on speed? E. Demonstration of induced voltage (by moving a conductor in a magnetic field and by a magnet near afixed coil)
8.4 Generators and mutual induction E. Electromagnetic induction
.
E. Use a CRO to observe output from a dynamo
E. Use a datalogger to graph output from a dynamo
E. Show that a motor can act as a generator and vice versa
E. Demonstrate mutual induction
8.5 Transformers E. Transforming the voltage Making model transformers
E. Demonstrate resistance heating and/or induction heating
Look at real transformers
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Pupil book spread Activities in Physics TRP Further work8.6 Generating electricity Literacy – Generating electricity from renewable
sourcesSATIS materials (available from ASE)
106 The design game
107 Ashton Island – A problem of renewable energy
109 Nuclear power
201 Energy from biomass
403 Britain’s energy sources
601 Electricity on demand
Also SATIS 16–19 materials
21 Energy from the wind
46 Energy from the waves
63 Biogas
Role play on siting a windfarm from Teaching and Learning about the Environment Pack 3 (UYSEG)available from ASE Booksales
Department of Trade and Industry provides data on fuel use in the UK www.dti.gov.uk/public/exp1.html
(Choose the Activities and Resources option, then Energy Statistics and then Energy in Brief)
Other information on renewable energy from University of Oregon (www.zebu.uoregon.edu/energy.html)
8.7 Power transmission E. Demonstration of low voltage model power lines
A1.1 Logic gates E. Logic circuits using AND, OR and NOT gates(Also A1.2–A1.4)
E. Make a moisture detector and pressure pad
E. Experimental work with relays
A1.2 Inputs and outputs E. Use AND and OR to switch on LEDs, motors
A1.3 Electronic systems
A1.4 More truth tables E. Set up bistables using NOR gates
E. Set up latch circuit – Practical work using NAND and NOR gates
A1.5 The bistable and latch
A1.6 Potential divider E. Measure the voltage across two parts of a potential divider for various resistance values
A1.7 Thermistors and LDRs E. Set up control circuits using LDRs and thermistors
A2.1 Refractive index ICT – Use a spreadsheet to show the relationship between angle of incidence and refraction (see 3.5)
E. Measure refractive index by sine/sine r
A2.2 How convex lenses work E. Finding f for lenses
A2.3 Uses of convex lenses V. Tacoma Bridge
ICT – Research on Tacoma Bridge collapse
Examine cameras and projectors
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Pupil book spread Activities in Physics TRP Further workA2.4 Resonance ICT – Spreadsheet to calculate wavelength from resonant length
E. Sonometer practical
A2.5 Resonance in strings E. Resonance in open and closed tubes
A2.6 Resonance in pipes
A2.7 Interferance E. Ripple tank for water waves showing reflection, refraction and diffraction
A2.8 The nature of light
A3.1 Linear motion E. Verify Principle of Conservation of Momentum using an airtrack
A3.2 Projectile motion
A3.3 Momentum
A3.4 Rockets and jets E. Make a model rocket
ICT – Look up data of rockets in current use
Use Internet to find out about jet engines
A3.5 Car crashes
A3.6 Measuring heat E. Measure specific heat capacity
A3.7 Efficiency E. Efficiency of a ramp E. Efficiency of motor and other simple machines
Use Internet to obtain information about efficiency of power stations, cars etc
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Introduction to Key Skills
In addition to GCSE double award (or separateaward) Science or GCSE Physics, students may becompleting a Key skills qualification. This involvesproducing a folio of evidence, and Science orPhysics can provide some of this evidence.
There are six Key skills.
Three Key skills that lead to a qualification:1 Application of numbers2 Communication3 Information technology
Three wider Key skills that are desirable, but donot form apart of a qualification:4 Improving own learning and performance5 Working with others6 Problem solving
If you want to find out more about Key skills,contact the QCA website:http://www.qca.org.uk/keyskills.
Key skills are at five levels: At GCSE Levels 1 and2 are appropriate.
Level 1 helps students develop the basic skills thatare important for Key skills competence, andrecognises their ability to apply these skills to meetgiven purposes within routine situations.
Level 2 builds on Level 1 by requiring students toextend their basic skills. It recognises their abilityto take responsibility for some decisions about howthey select and apply these skills to meet thedemands of largely straightforward tasks. Level 2corresponds to GCSE A–C.
The following sheets are designed so you can planopportunities for Key skills for each teachinggroup. A copy of this sheet could be given tostudents, to in-school Key skills Coordinators,Senior Management and external visitors,e.g. Ofsted Inspectors.
These sheets can be photocopied from theTeachers’ Resource Pack, or downloaded from theCD-ROM. If they are downloaded the name of theschool can be added in the header.
The OCR specification gives examples of whereKey skills can be met. The appropriateopportunities are added to the table followed by(1) if at Level 1, or (2) if at Level 2.
You should not try to find a large number ofopportunities. Students will have plenty ofopportunities in other subject areas. The onesyou suggest should be those that could providegood evidence.
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Application of numbersName of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must be able to interpret straightforward information carry out calculations, using whole numbers, simple decimals, fractions and
percentages to given levels of accuracy interpret the results of their calculations and present findings, using a chart and
diagram.
Level 2
Candidates must be able to carry through substantial activity that requiresthem to select information and methods to get the results they need carry out calculations involving two or more steps and numbers of any size,
including use of formulae, and check their methods and their levels of accuracy select ways to present their findings, including use of a graph, and to describe
methods and explain results.
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Communication
Name of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must be able to
take part in discussions about straightforward subjects
read and identify the main points and ideas from documents aboutstraightforward subjects
write about straightforward subjects.
Level 2
Candidates must be able to
help move discussions forward
give a short talk using an image to illustrate the main points
read and summarise information from extended documents
use a suitable structure and style when writing extended documents.
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xiv Information technologyName of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must be able to
find, enter, explore and develop relevant information
present information, including text, images and numbers, using appropriatelayouts, and save information
Level 2
Candidates must be able to
identify suitable sources, carry out effective searches and select relevantinformation
bring together, explore and develop information, and derive new information
present combined information, including text, images and numbers in aconsistent way.
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xv Improving own learning and performanceName of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must provide at least two examples of meeting the standard for LP1.1,LP1.2 and LP1.3.
LP1.1 Confirm their understanding of their short-term targets, and plan how thesewill be met, with the person setting them.
LP1.2 Follow their plan, using support given by others to help meet targets.
LP1.3 Review their progress and achievements in meeting targets with anappropriate person.
Level 2
Candidates must provide at least two examples of meeting the standard for LP2.1,LP2.2 and LP2.3.
LP2.1 Help set short-term targets with an appropriate person and plan how thesewill be met.
LP2.2 Take responsibility for some decisions about their learning, using their planand support from others to help meet targets.
LP2.3 Review progress with an appropriate person and provide evidence of theirachievements, including how they have used learning from one task to meet the
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Working with othersName of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must provide at least two examples of meeting the standard forWO1.1, WO1.2 and WO1.3 (one example must show they can work in one-to-onesituations, and one that they can work in group situations).
WO1.1 Confirm what needs to be done to achieve given objectives, includingresponsibilities and working arrangements.
WO1.2 Work with others towards achieving given objectives, carrying out tasks tomeet your responsibilities.
WO1.3 Identify progress and suggest ways of improving work with others to helpachieve given ojectives.
Level 2
Candidates must provide at least two examples of meeting the standard forWO2.1, WO2.2 and WO2.3 (one example must show they can work in one-to-onesituations, one that they can work in group situations).
WO2.1 Plan straightforward work with others, identifying objectives andclarifying responsibilities, and confirm working arrangements.
WO2.2 Work cooperatively with others towards achieving identified objectives,organising tasks to meet their responsibilities.
WO2.3 Exchange information on progress and agree ways of improving work withothers to help achieve objectives.
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Problem solvingName of school _________________________________________________________ Year Group _________________________________________________________
Teaching Group ______________________________________________ Date ___________________ Teacher ______________________________________________
Level 1
Candidates must provide at least two examples of meeting the standard for PS1.1,PS1.2 and PS1.3.
PS1.1 Confirm their understanding of the given problem with an appropriateperson and identify two options for solving it.
PS1.2 Plan and try out at least one option for solving the problem, using adviceand support given by others.
PS1.3 Check if the problem has been solved by following given methods anddescribe the results, including ways to improve their approach to problem solving.
Level 2
Candidates must provide at least two examples of meeting the standard for PS2.1,PS2.2 and PS2.3.
PS2.1 Identify a problem and come up with two options for solving it.
PS2.2 Plan and try out at least one option for solving the problem, obtainingsupport and making changes to their plan when needed.
PS2.3 Check if the problem has been solved by applying given methods, describeresults and explain their approach to problem solving.
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Allocation of time to different parts of thePhysics specification
Double Award Physics is made up of eight units, and the Extension A forPhysics Separate Science has three additional units. Students are requiredto study them all.
Different units require different lengths of time.
For Double Award, this analysis assumes 100 hours of Physics (along with100 hours of Biology and 100 hours of Chemistry).
The 100 hours must include:
Teaching Ideas and Evidence (Sc1.1). This is built into the StudentCoursebook.
Teaching and Assessing (Sc1.2). Internally assessed coursework.
This is best built into the course so that students have the opportunities todevelop their practical skills.
The time required for End-of-block tests and Mock and Terminal tests isnot included in this allocation of time.
It is important to remember that GCSE papers, both at Foundation andHigher levels, cannot examine KS3 content directly. The Check-upsections in the Student Coursebook are intended to remind students ofwhat they have already done. There is a summary sheet of KS3 for eachteaching block which may help.
A suggested breakdown of time is:
1. Electric circuits 6 hours2. Forces and energy 20 hours3. Wave properties 13 hours4. Using waves 17 hours5. Radioactivity 10 hours6. The Earth and Universe 10 hours7. Using electricity 11 hours8. Electromagnetism 13 hours
Separate Physics
This assumes an additional 50 hours.
A1 Electronics and control 16 hoursA2 Processing waves 19 hoursA3 More about forces and energy 15 hours
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Resistors connected in series
Aim
You are going to study the effect of connecting resistors in series.
What to do
1 Check that you have everything you need for the experiment.
2 Set your multimeter to the 2 kΩ resistance setting.3 Connect a single lead between the terminals, if there are more
than two terminals check with your teacher which two to use.
4 The meter should read zero, if it does not, ask your teacher forhelp.
5 Use two crocodile clips and two connecting leads to connectone resistor (R1) across the meter terminals as shown in Fig 1.
6 Repeat for a second resistor (R2).7 Make a note of the values in a table like the one shown below.
R1 in kΩ R2 in kΩ R1 and R2 in series in kΩ
8 Connect the two resistors in series, as shown in Fig 2 andmeasure the resistance of the combination.
9 Make a note of the value in the third column of the table.10 Repeat steps 5 to 9 for at least four more pairs of resistors.
Analysing your results
1 What can you say is always true when you compare the valueof the resistors on their own with the value when they areconnected in series?
2 Look carefully at the values in your table and try to find anumerical pattern in your results. You may find it useful to usea calculator.
3 What do you think will happen if you connect three resistors inseries?
4 Design a simple experiment to test your theory.
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Materials required
Digital multimeter Four crocodile clips
or two clipcomponent holders
Three connectingleads
Resistors
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R2R1
0.000
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Current–voltage graph for a metallic conductor
Aim
You are going to study the way in which the voltage across ametallic conductor affects the current flowing through it.
What to do
1 Check that you have everything you need for the experiment.2 Wrap the wire round a 30 cm ruler making sure that no part of
the wire touches another part.3 Attach a crocodile clip to each end of the wire to hold it in
place.4 Connect up the circuit as shown in the circuit diagram.5 Turn on the power supply and take a reading from both the
ammeter and voltmeter.6 Record the values in a table like the one printed below.
voltage
in Vcurrent
in Aresistance
in Ω
7 Use the equation resistance = voltage ÷ current to calculate theresistance of the piece of wire for this pair of results.
8 Repeat steps 5 to 7 for at least five more values of current.Do not use more than 12 V
Analysing your results
1 Look carefully at the values of resistance in your table.2 What can you say about the resistance of a metallic
conductor as the current flowing through it changes?3 Now draw a graph of voltage against current for a
metallic conductor using axes as shown opposite.
Extension work
4 Turn the wire round and find out whether the directionin which the current flows through the wire affects itsresistance.
Safety
The wire may get hot enough to burn you, especially if you use ashorter length than 2 m or too high a voltage/current setting.
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Materials required
2 m length ofconstantan wire
One voltmeter One ammeter Five connecting leads One power supply Two crocodile clips 30 cm ruler
wire
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Current–voltage graph for the filament ofa light bulb
Aim
You are going to study the way in which the voltage across thetungsten filament of a light bulb affects the current flowingthrough it.
What to do
1 Check that you have everything you need for the experiment.2 Connect up the circuit as shown in the circuit diagram.3 Turn on the power supply and take a reading from both the
ammeter and voltmeter.4 Record the values in a table like the one printed below.
voltage
in Vcurrent
in Aresistance
in Ω
5 Use the equation resistance = voltage ÷ current to calculate theresistance of the piece of wire for this pair of results.
6 Repeat steps 5 to 7 for at least 5 more values of current.Do not use more than 12 V
Analysing your results
1 Look carefully at the values of resistance in your table.2 What can you say about the resistance of the tungsten filament
of a light bulb as the current flowing through it changes?3 What do you think is causing this change in the resistance
of the filament?4 Now draw a graph of voltage against current for the
tungsten filament of a light bulb using axes as shownopposite.
5 Turn the bulb round and find out whether the direction inwhich the current flows through the filament affects itsresistance.
Safety
The light bulb will get hot enough to burn you. Keep fingers away!
© Heinemann Educational 2001 3
Physics TB1 Activity 1.3B
Materials required
Light bulb in holder One voltmeter One ammeter Five connecting leads One power supply
+ _
V
A
current (A)
volt
age
(V)
Graph of voltage against current for the filament of a light bulb
Physics TB1
M T?
Balancing metre rules
Aim
You are going to study the conditions needed to balance a metre rule.
What to do1 Check that you have everything you need for the experiment.
2 Fasten the boss to the stand about 20 cm above the base and fastenthe short metal rod in the boss so that it is directly above the base.
3 Use the hole drilled at the 50 cm mark of the metre rule tosupport the metre rule so that it is free to turn. Make sure thatthe zero end of the scale is on the left.
4 Slide a giant paper clip onto each end of the metre rule. Move onepaper clip to the 10 cm mark and put the other at the 70 cm mark.
5 Hold the metre rule steady at one end and hang 2 N onto thepaper clip at the 10 cm mark.
6 Hang 4 N onto the paper clip at the 10 cm mark.7 Let go of the metre rule but be ready to steady it. The chances
are that it will start to turn so get ready to catch it.8 Now slide one of the paper clips, with the weights still
attached, backwards and forwards until the metre rule isbalanced. You probably won’t have to move the clip very far.
9 Draw a table similar to the one printed below with enoughspace for ten sets of results.
weight 1, W1 in N weight 2, W2 in N distance 1, d1 in cm distance 2, d2 in cm
2 4
10 Use the scale on the metre rule to measure the distance fromthe 2 N weight to the metal rod, d1 and the distance from the4 N weight to the metal rod, d2.
11 Put the values for these two distances into the table.12 Repeat steps 4 to 11 for different weights and distances. There
are some situations where it seems to be impossible to balancethe metre rule, but you will find a way.
© Heinemann Educational 2001
Physics TB2 Activity 2.1
4
Materials required
Metre rule with hole Short metal rod Stand Boss Two giant paperclips Two sets of 100 g
slotted masses (thehanger and each masshas a weight of1 newton, N)
Stand Boss
Rod
1 N
1 N
d1
W1 W2
d2
M T?
Analysing your results
1 Look carefully at the values in your table and try to find a linkbetween the values of weight and distance. You will probablyfind it helpful to use a calculator.
2 Do you think that the data you have collected allows you tocome to a reliable conclusion about the effect of turning forces?
3 Suggest ways of making the data you collect more reliable.4 Predict what will happen if you have two weights on one side
of the metal rod and one on the other. Join with another groupand use the apparatus from both groups to test your prediction.
© Heinemann Educational 2001 5
Activity 2.1M T?
© Heinemann Educational 2001
Physics TB2
How speed affects stopping distance
Aim
You are going to find the distance that a vehicle travels whilestopping over a range of vehicle speeds.
What to do
1 Check that you have everything you need for the experiment.
2 Use wooden blocks to lift one end of the plank about 15 cm.Make sure the area beyond the end of the plank is clear.
3 Place the vehicle 0.30 m up the plank.
4 Let the vehicle go and time how long it takes for the vehicle toreach the bottom of the plank.
5 Measure the distance the vehicle travelsalong the floor before stopping. Measurethe distance from the front of thevehicle to the end of the plank.
6 Repeat results.7 Carry out the experiment again with
the vehicle starting at differentdistances up the plank.
8 Record your results in a suitable table.
Analysing your results
The following information may help you.
Average speed =distance travelled
time taken
final speed = 2 × average speed.
1 Plot a graph of stopping distance (y-axis)against speed of the vehicle at thebottom of the plank (on the x-axis).
2 Answer the following questions.Kim believes that the stopping distance is directly proportionalto the speed at the bottom of the plank.(a) What does Kim think will happen to the stopping distance
if the speed of the vehicle is doubled?(b) Do your results support Kim’s belief? What do you think?
Explain.3 Which of the following is most likely to cause errors in your
experiment?– Measuring the distance up the plank.– Measuring the time the vehicle takes to run down the
plank.– Measuring the stopping distance.
4 Would you have a better graph if you had taken more results?If so which results would you try to get?
© Heinemann Educational 2001
Physics TB2 Activity 2.2
6
Materials required
Wooden plank(1 m–1.5 m long)
Free-moving vehicle,e.g. toy car, dynamicstrolley
Metre rule Stopwatch Wooden blocks to
incline plank Calculator
0.30 m0.15 m
2.2
2.0
1.8
1.6
1.4
1.2
1.0
Stop
pin
g di
stan
ce, i
n m
0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6Speed, in m/s
M T?
Friction
Aim
You are going to find out how an object’s weight affects the frictionforce between it and the surface it rests upon.
What to do
1 Think how you would expect the frictional forces to changewhen the mass on the block increases.
2 Try to explain why, using your scientific knowledge.3 Check that you have everything you need for the experiment.4 Weigh the wooden block.5 Pull the wooden block along using the forcemeter (see diagram).
Record the force necessary to pull the block along at a steadyspeed.
6 Place 2 × 100 g masses on the block and repeatthe experiment.
7 Increase the mass on the block each time by200 g until the mass is 1000 g.
8 Record your results in an appropriate table.
Analysing your results
1 Plot a graph of the frictional force in N (on the y axis) againstthe total mass in g (on the x axis).
2 What can you conclude from your experiment?3 Does this support your original prediction? Use the data to
show this. If it does not support your prediction, how is itdifferent?
4 What are the most likely errors in your experiment?5 Suggest other factors that might affect the frictional force.
© Heinemann Educational 2001 7
Physics TB2 Activity 2.5
Materials required
Wooden block withscrew eye
Wooden board 0–5 N forcemeter Masses, 10 × 100 g Access to balance
2.5
2.0
1.5
1.0
0.5
0
Fric
tion
for
ce, i
n N
0 200 400 600 800 1000 1200Mass, in g
M T?
To investigate a factor which affects thedistance travelled by a projectileAim
A margarine tub is fired across the floor using an elastic band.
Your teacher will demonstrate this to you.
Your task is to identify the factors that affect how far the tub goesand then to study the effect of varying one of them.
What to do
Your task is in four parts
PlanningObtaining the EvidenceAnalysing the EvidenceEvaluation
First make a list of the factors that might affect how far the tub willtravel across the floor.Choose the factor you are going to investigate.Make a list of all the apparatus you will need.Write a plan on how you intend to carry out the investigation.What are you doing to ensure a fair test?Can you make a prediction?Try to support your prediction with your scientific knowledge andunderstanding.Plan a preliminary experiment and be prepared to make changes ifit does not work.
Now carry out your experiment collecting sufficient data.
Analyse these data. Do your findings support your prediction?
Finally evaluate your experiment. Did you collect enough data?Did you have any anomalous results? Could you suggest anyimprovements in your methods if you were to do it again?
Now write up your investigation.
© Heinemann Educational 2001
Physics TB2 Activity 2.7
8
M T?
Measuring reaction time
Aim
You are going to measure the time it takes you to react tosomething and relate this time to road safety.
What to do
1 You will need to work in pairs and will need to use the graphprinted below to measure your reaction time.
2 The graph shows how long a rule takes to fall differentdistances.
3 The graph shows that it takes 0.2 seconds for the rule to fall20 cm.
4 Copy the table below and use the graph to complete it.
distance fallen by
rule in cm
time taken in s
5
10
18
28
5 Check your answers with your teacher before going any further.6 One person is now going to let the rule go and the other person
is going to catch it, but the second person will not know whenthe rule is going to be released.
continued
© Heinemann Educational 2001 9
Physics TB2 Activity 2.9
Materials required
Half-metre rule
50
45
40
35
30
25
20
15
10
5
0
dist
ance
fal
len
(cm
)
0 0.05 0.1 0.15 0.2 0.25 0.30 0.35
time (s)
M T?
7 The first person holds the rule as shown in Fig 1, with the zeromark at the bottom, and then releases it without warning. Thesecond person has to catch it by moving their fingers together,Fig 2.
8 The distance marked ‘x’ on Fig 2 is the distance the rule hasfallen. Make a note of the distance.
9 Repeat ten times each and calculate the average of your results.
Analysing your results
1 Use the average distance fallen and the graph to measure theaverage time for you to stop the rule falling.
2 This is your reaction time. If you were riding a bicycle ordriving a car it might take you this time to put on the brakes ifyou saw a hazard in front of you.
3 Use the equation distance = speed × time to calculate how far avehicle travelling at different speeds would travel while youreacted to a hazard. Put the distances in a copy of the tableprinted below.
speed
in mph
speed
in m/s
distance travelled
in m
20 9
30 13
50 22
70 30
4 In a real driving situation your reaction time would probably bemuch longer.
© Heinemann Educational 2001
Physics TB2 Activity 2.9
10 10
Fig 1
M T?
Dropping steel ball bearings in oil
Aim
You are going to find the terminal velocity of ball bearings.
This experiment involves dropping steel ball bearings of twodifferent diameters into a tall measuring cylinder containing motoroil. The measuring cylinder is divided into four sections by threeelastic bands (see diagram). The time is taken for each ball bearingto fall from A to B and then from B to C. You can work out theterminal velocity in each case. From these results you can concludehow the terminal velocity changes as the diameter of the ballbearing changes.
What to do1 Check that you have the equipment required for the
experiment.2 Read ‘safety note’ and ask your teacher if you need anything
explaining.3 Put elastic bands around the measuring cylinder as shown in
the diagram. Make sure the distance between A and B and Band C is the same. Measure this distance.
4 Fill the measuring cylinder with motor oil.
Practical
5 Drop one of the ball bearings from above the centre of thesurface of the oil.
6 Start timing when the ball bearing passes A and take the timewhen ball bearing passes B and again when it passes C.
7 The ball bearing can be recovered by placing the magnet on theoutside of the measuring cylinder and moving it slowly up theoutside of the measuring cylinder until the ball bearing reachesthe top of the cylinder. It can then be dried with a tissue.
8 Repeat the experiment until you are satisfied with your results.9 Now carry out the same procedure with the smaller ball
bearing.
Do not throw the motor oil away at the end.
Obtaining and analysing results
1 Record the results of your experiments in a suitable table.Ask your teacher if you need help in devising a table.
2 Work out the terminal velocity for each ball bearing.3 How do you know that each ball bearing reaches its terminal
velocity?4 Have you collected enough evidence to be sure about the
relationship between the terminal velocity and the diameter ofthe ball bearing?
5 Suggest improvements that could be made to the procedure youhave used.
© Heinemann Educational 2001 11
Physics TB2 Activity 2.10A
11
Materials required
Measuring cylinder(500 cm3)
Fresh motor oil Small elastic bands Two small steel ball
bearings (one ofdiameter 4 mm andone smaller)
30 cm ruler Stopwatch Magnet Tissues
500 cm3
300 cm3
100 cm3
A
B
C
Safety
Avoid skin contact withmotor oil. Use towel ortissue. Wash hands afteryou have finished. Do notpour any oil into a sink ordrain.
M T?
Velocity–time graphs for falling balls
Aim
You are going to plot velocity–time graphs fora golf ball and a ping-pong ball being pulleddownwards by the force of gravity.
You can process your data and plot the graph manually or use aspreadsheet and linked graph-plotting package.
What to do1 Check that you have everything you need and set up your
apparatus, as shown in Fig 1.2 The ticker timer should be at least 1.5 m above the ground.3 Make sure that there is nothing to get in the way of the golf
ball as it falls.4 Cut a piece of ticker tape so that it is just shorter than the
distance between the time and floor.5 Fasten the tape to the ball and thread the tape through the
timer.6 Check that the ball falls freely and pulls the tape easily
through the timer.7 Repeat step 4, but turn on the power supply before letting the
ball fall.8 Repeat steps 2 to 7 using a ping-pong ball.
Obtaining and analysing results
1 Observe the dots made by the timer and measure the distancebetween each dot and the next, starting with the pair whichwere made first (see Fig 2).
2 Enter your results into a table like the one printed below, or asuitable spreadsheet.
3 The timer makes 50 dots every second so the time betweendots being made is 0.02 seconds.
4 The distance between dots is the displacement of the ball ineach 0.02 s time interval.
5 Using the equation velocity = displacement ÷ time calculatethe velocity for each 0.02 s time interval.
6 Use your results to plot graphs of velocity against time forboth balls.
7 What do the shape of the graphs tell you about the way inwhich the balls fall?
8 Use your ideas about the forces acting on the balls to explainthe shape of the graph.
time in s golf ball dist in mm golf ball vel in mm/s
0 0 0
0.02
0.04
© Heinemann Educational 2001
Physics TB2 Activity 2.10B
12
Resistive forces
Gravitational forces
Materials required
Ticker timer Ticker tape Golf ball Ping-pong ball Power supply Sellotape
1.5 m to ground
To power supply
Ticker timer clamped to stand
Fig 1
Experimentalarrangement
a
b
c
Fig 2a = displacement in first 0.02 sb = displacement in second 0.02 sc = displacement in third 0.02 s
M T?
What difference does a lid make?
Aim
You are going to investigate why fast food outlets bother to put alid on hot drinks.
What to do
1 Check that you have all you need for the experiment.
2 Measure 150 cm3 of cold water in a measuring cylinder andtransfer carefully to a polystyrene cup. Mark the level with awaterproof marker. Repeat for the other cup.
3 Drain the cups, set up the sensor equipment as shown.4 Fill each to the mark quickly with near-boiling water from a
kettle, fit the lid on one and begin recording.5 After a suitable time (e.g. 10–15 mins.) stop the recording and
print out the results.
Analysing your results1 Look at your results and see which vessel cooled quicker. Give
a scientific explanation for your answer based on methods ofheat transfer as well as saying why it is worth having a lid.
2 Examine the cooling rates by picking a suitable temperatureinterval, e.g. 80–75°C and reading off the time each vessel takesto cool through that range. Work out the average rate of coolingusing the formula given.
3 Compare the cooling rates for each vesseland work out how much faster one cools(e.g. the one without the lid cools threetimes as fast between 80 and 75°C.)
4 Examine if the relative rate of cooling isthe same for all temperature ranges.
5 Choose from the following and adapt themethod to answer one or more of thefollowing questionsa) What difference does the cup
material make? (N.B. see ‘safety’ note!)b) What difference does the cup size make?c) Is it worth using a double cup?d) Do shiny teapots keep the heat in better than dull ones?e) Do different metals lose heat at the same rate?f) What difference does it make if the seal on a vacuum flask
is broken?
© Heinemann Educational 2001 13
Physics TB2 Activity 2.11
13
Materials required
250 cm3 measuringcylinder
Waterproof marker Two polystyrene cups
and a lid Access to kettle for
hot water Two temperature
sensors and interface Computer and
datalogging software Access to other cups,
metal calorimetersand vacuum flasks(for extension work)
ComputerInterfacePolystyrene cups
Temperaturesensors Lid
Tem
pera
ture
Temperaturechange
Time (m)Time change
Cooling rate = Temperature change (˚C/min)Time change
Safety
Use only cups designed forvery hot liquids. Othertypes will collapse. takecare pouring boiling waterinto lightweight cups; it iseasy to tip them over.
M T?
Reflection of light by a plane mirror
Aim
You are going to study the behaviour of a ray of light when it isreflected by a plane (flat) mirror.
What to do
1 Check that you have everything you need for the experiment.
2 Draw a line, about 10 cm long, on the sheet of plain paper usinga ruler and then draw some short lines to represent thesilvering on the mirror (Fig 1).
3 Using a protractor draw a dashed line at right angles to themirror and label it ‘normal’ (Fig 2).
4 Draw a line like the one shown in Fig 3, measure the anglemarked, i and write down its value in a table like the oneprinted below.
angle i angle r
5 Use a stand for your mirror and arrange the mirror so that itstands vertically.
6 Put the mirror against the line marked AB. If you are using aplastic mirror put the front of the mirror against the line and ifyou are using a glass mirror put the back of the mirror againstthe line.
7 Connect your ray box to the power supply and use a single slitto make one ray of light shine along the paper.
8 Shine the ray of light along the line that starts at C so that ithits the mirror, you should see a ray of light reflected fromthe mirror.
9 Mark the position of this ray with two crosses (Fig 4).10 Draw in the line taken by this reflected ray and use your
protractor to measure the angle marked r (Fig 5). Write down itsvalue in the table.
11 Repeat steps 4 to 10 for at least five more lines where the anglei is different.
Analysing your results
1 What do your results tell you about angles i and r?2 Are your results reliable?3 How could you make your results more reliable4 Join with another group and arrange two mirrors to make a ray
of light follow the path shown in Fig 6.5 How could an arrangement like this be used?
© Heinemann Educational 2001
Physics TB3 Activity 3.4
1414
A
B
Fig 1
A
B
normalFig 2
AC
B
normal
i
Fig 3
AC
B
normal
i
+
+reflected
ray of light
Fig 4
AC
B
normal
ir
+
+reflected
ray of light
Fig 5
Fig 6
Materials required
Ray box Single slit Power supply Protractor Plain paper Pencil Ruler Plane mirror and
holder
M T?
Refraction of light by a perspex block
Aim
You are going to study the behaviour of a ray of light when it passesthrough a rectangular perspex block.
What to do
1 Check that you have everything you need for the experiment.2 Put the perspex block onto the piece of paper so that it rests on
its biggest face and then draw round the block in pencil (Fig 1).3 Remove the block and then using a protractor draw a line at
right angles to the perspex block and mark the end of the linewith a letter A (Fig 2).
4 Put the block back in place.5 Connect your ray box to the power supply and use a single slit
to make one ray of light shine along the paper.6 Shine the ray of light along the line that starts at A so that it
hits the block, you should see a ray of light coming out of theopposite side of the block.
7 Mark the position of this ray with two crosses (Fig 3).8 Remove the block and use the two crosses to draw in the path
of the ray of light as it emerges from the block.9 Repeat step 2, remove the block and then draw a line to the
block similar to the one in Fig 4. Label the line B.10 Shine the ray of light along the line that starts at B so that it
hits the block, you should again see a ray of light coming out ofthe opposite side of the block.
11 Repeat steps 7 and 8.
Analysing your results
1 Use the two diagrams you have drawn to predict the path takenby the ray as it travels through the block. Remember that lighttravels in straight lines.
2 What can you say about the behaviour of light as it travels fromone material into another?
3 Does the behaviour of the light depend on the angle at whichthe ray hits the boundary?
© Heinemann Educational 2001 15
Activity 3.5A
15
Materials required
Ray box Single slit Power supply Plain paper Perspex block Protractor Pencil and ruler
Fig 1
A
Fig 2
Path of ray of light
+
+
Fig 3
© Heinemann Educational 2001
Physics TB3
M T?
How does the angle change?
Aim
You are going to investigate therelationship between angle ofincidence and angle of refraction.
What to do
1 Check that you have everythingyou need for the experiment.
2 Place the block on a sheet ofplain paper, carefully trace round it and mark the centre of theflat face as accurately as possible.
3 Use a protractor to mark in the ‘normal’ line at 90° to thecentre point.
4 Mark in lines showing suitable angles of incidence (i)between 10° and 70°. Plan for a sensible number of values.Replace the block.
5 Use the ray box to shine a ray along each incidence line inturn. Mark the path of the ray as it leaves the block. Extendit back as shown and measure the angle of refraction (r) asaccurately as possible.
6 If you have time, repeat the experiment with ablock made from a different material.
Analysing your results
1 Find a straight-line (proportional) relationshipbetween the angles of incidence and refractionusing a spreadsheet.
2 Put in the values of the angles of incidence and refraction thenuse the X–Y plot function to examine the relationship. Tryother possibilities which involve maths functions of anglessuch as TANGENT, SINE or COSINE. Print out a graph whichshows the best straight-line relationship. Write out a formulato show this relationship.
3 Were your data accurate enough? What simple improvementscould be made to get more reliable data?
4 Find out what is meant by Refractive Index. What advantage isthere for people who wear glasses in having lenses made fromglass or plastic with a high refractive index?
Safety
Do not knock glass blocks against each other. Bits of glass may fly off.
© Heinemann Educational 2001
Physics TB3 Activity 3.5B
1616
Materials required
Glass or plasticsemi-circular block
Sheet of A3 paper Raybox with narrow
slit Protractor Ruler Sharp pencil Access to computer
with spreadsheetpackage such asEXCEL
Narrow slits
Ray box
Semi-circular block
Narrow light beam
Normal10˚
Guide linesGuide lines
Outlineof block
also A2.1
Angle of incidence
Angle of refraction
ir
M T?
The visible spectrum
Aim
You are going to observe that white light can be split into itsconstituent colours and relate the colour of light to the wavelengthand frequency of the electromagnetic waves. This experiment willhelp you to develop practical and observational skills.
What to do
1 Check that you have everything you need for the experiment.
2 Set up the apparatus as in the figure.3 Direct a beam of light on to the face of the prism and
observe the light that leaves the opposite face byplacing the screen in a suitable position.
4 Observe the appearance of the spectrum.5 Write down the colours in the order in which they
appear on the screen, starting with red.6 Which colour of visible light undergoes the greatest
change in direction?7 Where does the change in direction take place?8 Note that the change in direction is caused by the change in
speed when light passes from one material into another.
Analysing your results
1 How does the speed of light change as it passes into the prism?2 Which colour of light has the greatest change in speed as it
passes into the prism?3 Which colour of light has the greatest speed in the prism?4 The table shows typical wavelengths and frequencies of red,
green and blue light.
colour typical wavelength in m typical frequency in Hz
red 6.0 × 10-7
5.0 × 1014
green 5.0 × 10-7
6.0 × 1014
blue 4.0 × 10-7
7.5 × 1014
Complete the sentence:As the wavelength of light increases, its frequency_______________.
5 Which colour of light has the (i) longest wavelength?(ii) greatest frequency?
6 What is the relationship between the change in speed of light asit passes into and out of a prism and its wavelength?
© Heinemann Educational 2001 17
Physics TB4 Activity 4.1
17
Materials required
Power supply 12 V, 24 W lamp in
holder Slit to produce a
narrow beam Isosceles prism White screen which
will stand vertically
White lightPrism
White screen
M T?
Where do the earthquakes happen?
Aim
You are going to use the internet to find data on recentearthquakes, examine the evidence they provide for tectonic platetheory and use ICT to produce a report.
What to do
1 Prepare a presentation which is part of a larger presentation onthe topic of ‘Earthquakes’. Your section of the work is ‘thePattern of Recent Earthquakes’ and it is important that most ofyour information is as up to date as possible. You can decideexactly what is meant by ‘recent’ and you are at liberty to addearlier information which will reinforce your findings.
2 Your presentation can be in the form of
a) a computer based presentation package (e.g. Powerpoint)
b) a talk which uses OHP transparencies
c) a magazine article.
In each case, you will need to provide copies of all text, graphand diagram work.
3 Your target audience will want to know answers to thefollowing:
How many earthquakes are there worldwide each day? Which has been the biggest one recently? How are they different in their destructive power? How is the destructive power calculated? Where do they tend to occur and what does this tell us
about the structure of the Earth? How are they located? What earthquakes have we had in this country lately and
why don’t we get very big ones? What is happening about predicting earthquakes?
4 You should begin your search by using a search engine to findsites which contain ‘earthquake’ but use other key words tonarrow down the search so that you find a small number ofsites which are relevant to your task and which can beexamined easily.
5 When you have found useful information, select carefully whatyou need and store it in a form which can be used in your finalpresentation. If in doubt, save it, you can always discard itlater. Keep a record of the sites you use so that you can quotethem in your report or go back to them for extra information ifyou need to.
© Heinemann Educational 2001
Physics TB4 Activity 4.6–4.8
1818
ICT required
Computer with– internet connection– word processor– spreadsheet– desktop publisher– presentation
package,e.g. Powerpoint
– access to colourprinter
M T?
Absorption of radioactivity: Teacherdemonstration
Aim
In this experiment you are going to distinguishbetween the three main types of radioactiveemission in terms of their penetration. You will beable to relate the penetration of radioactiveemissions to the size of the emission and to developskills in the safe handling of radioactive materials.
What to do1 Describe the key points in the procedure.
2 Give two safety precautions that should always be observedwhen handling radioactive materials.
3 Measure the total number of counts in 1 minute and record theresults in the table, at the bottom of the page.
Analysing your results
1 Which of the three sources was decaying at the greatest rate?Explain how you can tell.
2 Which source has the least penetration?3 Alpha sources are used in domestic smoke alarms. Explain why
the radiation from these sources does not present a threat tothe people who live in the house.
4 Explain whether it is valid to conclude that alpha radiation istotally absorbed by a 5 cm air gap.
5 Suggest why the count rate detected from the beta and gammasources is reduced by a 5 mm air gap.
source absorber number of counts in 1 minute
background radiation none
alpha none
5 cm air
3 mm aluminium
beta none
5 cm air
3 mm aluminium
2 mm lead
gamma none
5 cm air
3 mm aluminium
2 mm lead
2 cm lead
© Heinemann Educational 2001 19
Physics TB5 Activity 5.2
Radioactive source Absorber Counter
Detector (GM tube)
M T?
Simulation of radioactive decay
Aim
You are going to simulate radioactive decay using a random numbergenerator and then use the data to find a half-life.
What to do
1 Set the random number generator to select 240 numbers atrandom between 1 and 6. This means setting the limits at 0and 7.
2 Generate the random numbers and print them out.3 Count up the number of sixes in the list. Suppose there are x
sixes chosen.4 Repeat but generate (240−x) numbers. Print these out.5 Count up the number of sixes in the list. Suppose there are y
sixes.6 Repeat but generate (240−x−y) numbers.7 Continue repeating the procedure until you are generating less
than 25 numbers (i.e. about 10% of the number you startedwith).
8 Record your results in a suitable table.
Analysing your results
1 Plot a graph of the number of random numbers generated (onthe y-axis) against the number of times numbers are generated(on the x-axis).
2 Describe how you would monitor the activity of a radioactivesample.
3 Describe the shape of the graph.4 The half-life is the average number of times numbers have to
be generated for the number to fall to half its value, e.g. 240 to120 or 180 to 90. Take four different starting numbers and findthe average number of number generations required each timeto get to half the original value. Work out an average.
5 Suggest how this experiment could be adapted to improve theprecision of the results.
© Heinemann Educational 2001
Physics TB5 Activity 5.3
20
Materials required
Computer Random number
generator programme Access to a printer
M T?
Use of a van de Graaff generator to linkelectric charge and current:Teacher demonstration
Aim
In this experiment you will discover that an electric current is aflow of electric charge. You will develop observational skills andanalyse how the charge is carried by a conducting ball. You willalso discover how to change the size of the electric currentproduced.
Safety
This is a teacher demonstrationexperiment only.
The dome of the van de Graaffgenerator can become chargedto a very high voltage.
The van de Graaff generatormust not be touched while theexperiment is in progress.
The dome of the van de Graaffgenerator must not be touchedafter the experiment until theteacher has checked that it isfully discharged.
What to do
1 Describe the key points in the procedure.2 Answer the following questions.
1 Explain why the sensitive ammeter indicates a current.2 Mark the charges, if any, on the ball at each stage of its motion
as shown in the diagrams below.
3 Use the diagrams to explain why the ball keeps oscillatingbetween the plates.
4 What happens when the plates are moved closer together to(a) the movement of the ball?(b) the ammeter reading?
Account for the changes you have mentioned in (a) and (b).
© Heinemann Educational 2001 21
Physics TB7 Activity 7.3
van de Graaffgenerator
Small conducting ball suspended by nylon thread
2 metal plates clamped by insulating handles H
H H
Sensitive ammeter(e.g. light beam galvanometer)
+++
–––
+++
–––
+++
–––
(a) (b) (c)
M T?
How fast does the motor go?
Aim
You are going to use datalogging to look at the speed of a motor andhow it changes with current, voltage and load.
What to do
1 Make sure that you have all that you need for the experiment.2 Set up the equipment as shown above.
3 Set the computer to record for 30 seconds.4 Select a low voltage, enough to get the motor turning slowly,
switch on the motor and begin recording.
5 Note values of voltage and current.6 Repeat for different voltage/current settings. You will need to
choose the values and the range which would be appropriate forreliable results.
7 Calculate the speed of the motor foreach run as in the diagram below.
8 Tabulate these values and plotgraphs of motor speed againstcurrent, voltage and powerconsumption. You may wish to usea spreadsheet to do this section ofthe task, as well as the calculationof motor speed.
Analysing your results
1 What relationship does the motor speed have to the linked variables voltage, current andpower?
2 Use the experience gained from using the basic method to plan a variation which looks at theeffect of ‘load’ on the motor speed at a given voltage.
© Heinemann Educational 2001
Physics TB8 Activity 8.2
22
Computer
Interface
Light unit
Light sensor
12V
12VVariablepower supply A
V
Motor
Flywheelwith slit
Lig
ht
leve
l
Time (s)
Time for 10 gaps • Note time (T) for 10 gaps
• Time for 1 rotation = T10
T10
• Rotations per minute = =60
T600
( )
Materials required
Computer withdatalogging softwareand interface
Printer Light sensor and light
unit Ammeter Voltmeter Variable power
supply Electric motor fitted
with flywheel Suitable leads Access to a
spreadsheet such asExcel
Safety
Keep fingers, ties, long hairetc. well away fromspinning flywheel.
M T?
How does voltage depend on speed?
Aim
You are going to use datalogging to link the size of an induced emfwith the speed of change of magnetic field using a voltage sensorand light gates.
What to do1 Make sure that you have all you need for the experiment.2 Set up the apparatus as shown, with the light gates being a known distance (e.g. 15 cm) apart.3 Set the datalogging software to record the voltage across the coil and the time between the
light gates being activated. If the software allows it, set it to calculate the speed of themagnet between the light gates, otherwise you will have to calculate the speed manuallyfrom the time value for each experiment.
4 Set a recording time of 5 seconds or as near above this as thesoftware allows.
5 Start recording and, after a delay of one second, drop themagnet through the tube.
6 Note from the computer, the time or speed of the magnetand the peak-to-peak induced voltage.
7 Repeat the experiment several times, each time increasingthe distance between the end of the tube and the coil so thatthe speed of the magnet increases. You will have to decidethe number of different speeds and what to do if you wish toincrease the range of speeds.
Analysing your results1 Plot a graph of induced voltage against speed to determine the relationship between the two.
You could put the results into a spreadsheet such as ‘Excel’ and use this to draw a line of bestfit.
2 Determine a mathematical relationship between the speed and induced voltage.3 Explain the form of the induced voltage recording.4 Why does the magnet’s speed not increase linearly with distance?5 The induced voltage recording is not always symmetrical about the null point. Suggest
reasons for this.6 Could the light gates be closer to get a more reliable measure of the speed? Explain your reasons.
© Heinemann Educational 2001 23
Physics TB8 Activity 8.3
Computer
Interface
Coilunit
Magnet
Tube
Foam rubber
Pea
k-t
o-pe
akvo
ltag
e
Voltage
Time
Materials required
Computer anddatalogging software
Glass or plastic tubeapproximately 1.5 mlong by 30 mmdiameter
Light gates Voltage sensor Coil of wire with
known number ofturns
Small cylindricalmagnet
Foam rubber
M T?
Electromagnetic induction
Aim
You are going to investigate electromagnetic induction to demonstratethat a voltage is induced in a conductor when the magnetic fieldthrough it changes. You will find out how the size of the inducedvoltage depends on the rate at which the magnetic field changes andalso how the direction of the induced voltage can be reversed. Thiswill help you to develop practical and observational skills.
What to do1 Make sure you have all the equipment for the experiment.
2 Wind a coil of 2–3 cm diameter and 15–20 turns and connect itto a sensitive ammeter which can detect currents in eitherdirection.
3 Complete the table of results, by comparing the ammeterdeflection in each case.
action ammeter indication
N pole moved slowly towards coil
N pole moved rapidly towards coil
magnet held stationary inside coil
S pole moved towards coil
current in primary coil switched on
current in primary coil remains on
current in primary coil switched off
Analysing your results
1 How is the size of the induced voltage affected by the speed ofmovement of the magnet?
2 State two ways of reversing the direction of the voltage inducedby moving a magnet towards a coil of wire.
3 Explain why there is no induced voltage when the magnet isstationary inside the coil.
4 Explain why a voltage is induced in the secondary coil when adirect current is switched on in the primary coil.
5 Explain why there is no induced voltage in the secondary coilwhen a steady current passes in the primary coil.
6 Explain why, when the current in the primary is switched off, thevoltage induced in the secondary coil is in the opposite directionto that when the current in the primary coil is switched on.
7 If the current in the primary coil were to be switched on and offrepeatedly, what type of current would pass in the secondary coil?
© Heinemann Educational 2001
Physics TB8 Activity 8.4
24
Sensitive ammeterPrimary
coilSecondary
coil
Materials required
2 × 1 metre length ofsingle strand wire
Sensitive ammeter Strong bar magnet 1 pair of c-cores 1.5 V d.c. cell in
holder A switch Connecting leads and
crocodile clips Wire cutters/strippers
M T?
Transforming the voltage
Aim
You are going to perform an experiment to help you understandthat electromagnetic induction occurs when the magnetic fieldthrough a conductor changes. You will also develop observationalskills and find out the difference in action and constructionbetween a step-up and a step-down transformer. This will helpyou to relate step-up and step-down transformers to someeveryday uses.
What to do
1 Wind two separate 15 turn coils of wire onto c-cores as in thediagram.
2 Connect one coil to a lamp, the brightness of which indicatesthe size of the induced voltage.
3 Connect a d.c. source to the primary coil and note that thelamp does not light.
4 Connect a low-voltage a.c. source to the coil and use thebrightness of the lamp as a reference.
5 Change the number of turns of wire on the secondary coil andnote the brightness of the lamp.
continued
© Heinemann Educational 2001 25
Physics TB8 Activity 8.5
Materials required
Coils of wire Two c-cores Lamp d.c. source Low-voltage a.c.
source
Safety
In these experiments,you may need tolengthen the wire thatyou are using.It is permissible to dothis by joining twowires together, bytwisting the bared endsbut if you do this, coverthe join with insulatingtape.This method of joiningwires is onlypermissible because thevoltages used are lowand the connections areonly temporary.DO NOT ever use thismethod of joining wiresthat carry mainsvoltages as this couldresult in a fire orsomeone receiving afatal electric shock.
Primary coil
Secondarycoil
Iron c-cores
1.5 V d.c.supply
2 V a.c.supply
M T?
Obtaining and analysing evidence
1 Complete the table of results, at the bottom of the page.2 A voltage is induced in a conductor when the magnetic field
through it changes. Explain why the lamp does not light whena direct voltage is connected to the primary coil.
input (primary)
voltage
number of
primary turns
number of
secondary turns
lamp brightness (off, dim,
normal or bright)
1.5 V d.c. 15 15
2.0 V a.c. 15 15 normal
2.0 V a.c. 15 10
2.0 V a.c. 15 20
2.0 V a.c. 15 25
2.0 V a.c. 15 30
3 Explain why the lamp lights when an alternating voltage isapplied to the primary coil.
4 A step-down transformer decreases the size of an alternatingvoltage. What is the relationship between the numbers of turnson the primary and secondary coils in a step-down transformer?
5 A step-up transformer increases the size of an alternatingvoltage. What is the relationship between the numbers of turnson the primary and secondary coils in a step-up transformer?
6 Which type of transformer is used:(a) to increase the mains voltage from 240 V to 5000 V to
accelerate the electrons in a television tube?(b) to decrease the mains voltage from 240 V to 12 V to operate
a low-voltage garden light?
© Heinemann Educational 2001
Physics TB8 Activity 8.5
26
M T?
Generating electricity from renewablesources
In recent years most of the electricity has been generated fromburning fossil fuels such as coal and natural gas. Only about 2–3%has been generated from renewable sources.
The UK Government has set targets:
to produce 5% of the electricity used from renewable sourcesby 2003
to produce 10% by 2010.
Three ways of producing electricity from renewable sources are touse water, biomass and wind.
Download Sustainable Power – at a Price from ElectricityAssociation (www.electricity.org.uk).This is to be used as referencematerial but students may seek information elsewhere. It may bebeneficial if students are given homework to read the article and todo some research themselves.
Divide students into four groups.Each group is allocated one of thefollowing.
1. Supporters of generating electricity from coal and natural gas.2. Supporters of generating electricity from water.3. Supporters of generating electricity from biomass.4. Supporters of generating electricity from wind.
Each group should appoint a leader and then under his/herleadership produce a table listing the advantages of their method ofgenerating electricity and the disadvantages of the others.
They then write a report promoting their fuel. This should bebetween 200 and 300 words. Approximately an hour should bespent on this.
One member of each group then reads out their report.
The whole class is then asked to vote on the best method forgenerating electricity in the future, on the evidence provided by thereports.
Follow up:
Each student writes an essay on the fuels that are available forgenerating electricity in the 21st century.
N.B. There are no Teachers’ and technicians’ notes for this activity.
© Heinemann Educational 2001 27
Physics TB8 Literacy activity 8.6
M ?
Logic circuits using AND, OR and NOTgates
Aim
You will set up logic circuits using AND, OR and NOT gates for avariety of input sensors, such as light, temperature and moisturesensors and draw up results in the form of truth tables.
What to do
1 Set up the logic circuits shown below, using the input sensorssuggested. (Your teacher will tell you how to connect up theparticular type of logic unit in your laboratory.)
2 For each circuit complete the truth table, where 1 represents ahigh signal and 0 a low signal.
3 If time permits repeat for other combinations of input sensors.4 (H) Combine AND and NOT and OR and NOT gates.5 (H) Repeat using NAND and NOR gates.6 Remember: the resistance of a light dependent resistor (LDR) is
low in the light and the resistance of a thermistor is low whenhot.
Analysing your results
1 Complete the following truth tables.
AND gate truth table Input sensors – light and temperature sensors
Inputs Output
A B
0 0
0 1
1 0
1 1
OR gate truth table Input sensors – two light sensors
Inputs Output
A B
0 0
0 1
1 0
1 1
© Heinemann Educational 2001
Physics TBA1 Activity A1.1–A1.3
28
Materials required
Low-voltage (5 V)power supply
AND, OR and NOTgates – at least one ofeach
At least two inputsensors chosen from:light, temperature,moisture sensors
Suitable output suchas LED, lamps orbuzzer
Connecting leads (H) NAND and NOR
gates – at least one ofeach
Extra gates and inputsensors if you go onto combine logicgates
Safety
Electronics apparatusmust only be used witha low-voltage powersupply (5 V). Alwaysmake sure that thepower is switched offwhen setting up orchanging your circuits.Get your teacher tocheck your circuitsbefore switching on.
AND gate
InputsA
BOutput
OR gate
InputsA
BOutput
M T?
NOT gate truth table Input sensor: (i) light sensor(ii) temperature sensor
(i)
Input Output
0
1
(ii)
Input Output
0
1
2 Suggestions for further experimental work:(a) Repeat the above experiments using other combinations of
sensors.(b) Suggest practical applications for each logic system.(c) (i) Combine two or more logic gates and draw up a truth
table from your results.(ii) See if you can deduce the result using the truth tables
for AND, OR and NOT gates obtained previously.
H level
1 (a) Combine NOT and AND gates and produce a truth tablefrom your results.
(b) Use a NAND gate and show that the truth table obtained isthe same as that in (a).
2 (a) Combine NOT and OR gates and produce a truth tablefrom your results.
(b) Use a NOR gate and show that the truth table obtained isthe same as that in (a).
3 (a) Combine two or more logic gates, including at least oneNAND and/or NOR gate, and draw up a truth table fromyour results.
(b) See if you can deduce the outcome using the truth tablesobtained previously.
Physics TBA1 Activity A1.1–A1.3
© Heinemann Educational 2001 2929
NOT gate
Input Output
M T?
Measuring specific heat capacity
Aim
You are going to calculate the amount of energy transferred fromelectricity to heat by an immersion heater and develop skills inapplication of number which will enable you to understand thatdifferent materials require different amounts of energy to raise thetemperature by the same amount.
What to do
1 Set up theapparatus asin thediagram.
2 Using a 1 kg metal block, record the intial temperature.3 Switch on the immersion heater until the temperature has
risen by about 10°C.
4 Record the current, voltage and time for which the heater isswitched on.
5 Record the maximum temperature reached after the heater hasbeen switched off.
6 Repeat the procedure for other metals and complete the table atthe bottom of the page.
Analysing your results
1 Explain why a temperature rise of about 10°C is more reliablethan one of 5°C or 20°C.
2 During heating, energy is lost to the surroundings. Describehow this energy loss occurs.
3 Suggest how energy loss to the surroundings could be reduced.4 What effect does the energy loss have on the measured values
of specific heat capacity compared to the actual values?5 At a given temperature, the average kinetic energy of the atoms
in a metal is the same for all metals. Suggest why the differentmetals have different specific heat capacities.
material initial temp.
in °C
final temp.
in °C
current in A voltage in V time in s specific heat capacity
= (current × voltage × time)
÷ (1 kg × temperature rise)
brass
© Heinemann Educational 2001
Physics TBA3 Activity A3.6
30
Materials required
1 kg blocks ofaluminium, iron,brass and copper
Stopwatch Laboratory
thermometer 12 V power supply 0–5 A ammeter 0–15 V voltmeter 12 V, 24 W
immersion heater
Safety
The heater becomesvery hot and it willburn your skin if youtouch it, so only havethe heater switched onwhen it is inside themetal block and leavethe heater inside theblock until it hascooled. After removingthe heater from theblock, handle carefully,do not touch theelement, and place on aheat-resistant mat.
Thermometer Circuit diagram
12V supplyHeater
Stopwatch
00.00
+
A
V
M T?
Efficiency of a ramp
Aim
In this experiment you will calculate the amount of work donewhen a weight is lifted vertically in the Earth’s gravitational field.This will help you to develop observational skills and practiceusing the relationship between efficiency and work. You willalso understand the advantages and disadvantages of using aramp as a machine.
What to do
1 Write a plan for this experiment. Make alist of the steps you are going to follow.Include scientific knowledge in your planand try to use this to make a prediction.
2 Measure the energy input needed to raise aload by lifting it vertically and by draggingit up a slope for different heights of theramp.
3 Complete the table of results at the bottom of the page.
Analysing your results
1 Which requires more work, lifting the mass or dragging it upthe slope?
2 Explain why this method requires more work.3 Does the mass gain more energy when it is lifted, or more
energy when it is dragged or the same amount of energywhether it is lifted or dragged?
4 Explain why heavy objects are loaded into vans or lorries bydragging them up a slope rather than by lifting them.
5 What is the disadvantage of dragging a heavy object up a sloperather than lifting it?
6 What is the relationship between the efficiency of the ramp andthe steepness of the slope?
height of ramp,
h in m
force needed to lift
mass vertically
through height
h in N
work done in lifting
mass vertically in J
force required to
drag mass through
distance s up slope
in N
work done in
dragging mass up
slope in J
efficiency of ramp =
work done in lifting
mass ÷ work done in
dragging mass
0.10
0.20
0.30
0.40
0.50
© Heinemann Educational 2001 31
Physics TBA3 Activity A3.7
Materials required
Wooden board,approximately 1mlong
1 kg mass Metre rule 0–10 N forcemeter Wooden blocks for
raising one end of theramp
1 Kg mass Force meter
Distance s
Verticalheight h
M T?
Resistors connected in series
Aim
This experiment enables students to study theeffect of connecting resistors in series.
Activity procedure1 Students use a multimeter to measure the
resistance of two resistors on their own andthen connect them in series and measure theresistance of the combination of resistors.
2 Pupils compare the individual values for tworesistors with the value when they areconnected in series and are expected todiscover what the relationship between thevalues is.
3 There is an opportunity to extend the enquiryto three resistors connected in series.
Other resources
Physics Book pp.4–9Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Removing the table allows access to skill Obut the skill level involved is low.
It will be necessary to change the instructionsregarding which scale on the multimeter touse if the meter does not have a 2 kΩ scale.
Reference to either clip component holders orcrocodile clips can be deleted.
Running the activity
A demonstration of the multimeter in use will bevery helpful.
Students may need help in interpreting the displayon the multimeter.
Multimeters
The choice of range for the multimeter will varyfrom one manufacturer to another. Matching therange of resistor value to the multimeter will benecessary.
Choice of resistors
Any 0.5 W metal film resistors can be used.
Values can be chosen to keep the value of thecombination below the maximum valuemeasurable.
The following selection from the E12 series issuggested for different multimeter ranges.
Twenty of each of the values suggested will beadequate for a group of 30 pupils.
Multimeter range Resistor values
1 kΩ K10, K12, K15, K18, K22, K27,
K33, K39, K47
2 kΩ K18, K22, K27, K33, K39, K47,
K56, K68, K82
Physics TB1 Teachers’ and technicians’ notes 1.1
© Heinemann Educational 200132
Materials required per
group
per ( )
groups
Digital multimeter 1
Crocodile clips 4
Clip component holders 2
Connecting leads 3
Resistors see below
M ? A
Current–voltage graph for a metallic conductor
Aim
This experiment enables students to investigatethe relationship between voltage and current for ametallic conductor.
Students use a circuit diagram to connect anelectrical circuit, tabulate results and process themboth numerically and graphically before drawingconclusions from their results.
Activity procedure1 Students connect a length of metallic
conductor into a circuit and measure currentthrough and voltage across the conductor.
2 The voltage is varied and the correspondingvalues of current and voltage are recorded.
Other resources
Physics Book (pp.8–9)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
The range of voltages and the number ofreadings can be varied.
Running the activity
Pupils shoud be aware of the safety warning.
The use of constantan/eureka minimises the effectof changes in temperature on the resistance of theconductor.
Safety
Two metre lengths of 28 swg constantan willremain cool to the touch when voltages below 16 Vare used, but very short lengths may get red hot.
Sample results
voltage (in V) current (in A) resistance (in Ω)
0 0
1 0.03 33
2 0.06 33
3 0.08 38
4 0.11 36
5 0.14 36
6 0.16 38
7 0.19 37
8 0.22 36
9 0.24 38
10 0.27 37
11 0.3 37
12 0.33 36
Physics TB1 Teachers’ and technicians’ notes 1.3A
© Heinemann Educational 2001 33
Materials required per
group
per ( )
groups
2 m length wire 1
Voltmeter 1
Ammeter 1
Connecting leads 5
Crocodile clips 2
30 cm ruler 1
Vol
tage
(V)
14
12
10
8
6
4
2
00 0.05 0.1 0.15 0.2 0.25 0.3 0.35
Current (A)
M ? A
Current–voltage graph for the filament ofa light bulb
Aim
This experiment enables students to investigatethe relationship between voltage and current forthe tungsten filament of a light bulb.
Pupils use a circuit diagram to connect anelectrical circuit, tabulate results and process themboth numerically and graphically before drawingconclusions from their results.
Activity procedure1 Students connect a light bulb into a circuit
and measure current through and voltageacross the filament.
2 The voltage is varied and the correspondingvalues of current and voltage are recorded.
Other resources
Physics Book (p.8–9)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
12 V 24 W light bulbs are suitable for thisexperiment.
If dedicated holders are not available, an optical raybox with bulb could be substituted.
Sample results
voltage (in V) current (in A) resistance (in Ω)
0 0
1 0.61 1.64
2 0.81 2.47
3 0.98 3.06
4 1.13 3.54
5 1.26 3.97
6 1.40 4.29
7 1.50 4.67
8 1.61 4.97
9 1.71 5.26
10 1.81 5.52
11 1.90 5.79
Safety
A light bulb will get hot enough to burn you. Keepfingers away.
Physics TB1 Teachers’ and technicians’ notes 1.3B
© Heinemann Educational 200134
Materials required per
group
per ( )
groups
Light bulb in holder 1
Voltmeter 1
Ammeter 1
Connecting leads 5
Power supply 1
Vol
tage
(V)
14
12
10
8
6
4
2
0
0 0.5 1 1.5 2 2.5
Current (A)
M ? A
Balancing metre rules
Aim
This experiment enables students to investigatethe conditions needed to balance a metre ruleexperiencing opposing moments.
The data collected have to be processed and lead toan understanding of the principle of moments.
Activity procedure1 Students balance a metre rule using forces
provided by slotted masses suspended fromgiant paperclips that are able to move alongthe rule. The rule itself is pivoted at itsmid-point so its weight provides no turningmoment.
2 The sizes of the forces involved and thedistances from the pivot are noted and used todiscover that, within the limits ofexperimental error W1 × d1 = W2 × d2.
Other resources
Physics Book (pp.14–15)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Removing the table allows access to skill Obut the skill level involved is low.
Running the activity
A demonstration of the procedure may be helpful.
It is important that pupils appreciate that the masshanger on its own has a weight of 1 N.
The suggested position for the boss on the standreduces the risk of the metre rule spinningviolently when unbalanced.
Steel rod with a diameter of 4 mm cut into 5 cmlengths is suitable for making the short metal rods.
A hole should be drilled in the metre rule at the50 cm mark using a twist drill 0.5 mm larger thanthe diameter of the metal rod.
Giant paperclips are approximately 7.5 cm long and1.5 cm wide. They slide easily over a metre rule.
Analysing your results
Students should find that the metre rule isbalanced when clockwise and anticlockwisemoments are the same. This can be expressed as
W1 × d1 = W2 × d2
Where there are two weights on one side, the sumof the moments should balance the moment on theother side
(W1 × d1) + (W2 × d2) = W3 × d3
Physics TB2 Teachers’ and technicians’ notes 2.1
© Heinemann Educational 2001 35
Materials required per
group
per ( )
groups
Drilled metre rule 1
Short metal rod 1
Boss 1
Giant paperclips 52
100 g slotted masses 2
M ? A
How speed affects stopping distance
Activity procedure1 Students run a model car down an inclined
plank starting it from different distances upthe plank.
2 The time is measured for the car to reach thebottom of the plank. Students measure thedistance the car travels before coming to rest.
3 From these measurements students can workout the speed of the car.
Other resources
Physics Book (pp.16–17).
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
This activity can provide useful practical workfor a wide range of abilities.
For lower abilities, restrict the activity to oneangle and provide a blank copy of the table ofresults. You could also provide an Excelspreadsheet where they input their results andaverage times, average speeds, speeds at thebottom and average distances are calculated.
For higher ability pupils, the activity can beextended by getting them to alter the angle ofthe plank. Alternatively, masses can be addedto the car. Then predictions can be made basedon f=ma. Now there are full opportunities forPOAE.
Running the activity
Pupils need to ensure that there is enough space atthe end of the plank for the car to run to standstill.The same surface should be used for allmeasurements.
Sample graph
Answers
2 (a) She thinks it will double the distance.(b) No it is greater than Kim thinks. Distance
is proportional to speed squared.3 Measuring the time.4 Repeat with more distances, especially 1.1 m/s
and above.
Safety
Poorly supported planks may fall on toes andfingers. Work on floor to avoid heavy dynamicstrolleys falling off benches. Use ‘catch boxes’ of, forexample, scrap polystyrene or foam rubber at theend of the steeply inclined runways.
Physics TB2 Teachers’ and technicians’ notes 2.2
© Heinemann Educational 200136
Materials required per
group
per ( )
groups
Wooden plank (1 m–1.5 m long) 1
Free-moving vehicle e,g. toy car, dynamics
trolley
1
Metre rule 1
Stopwatch 1
Wooden blocks to incline plank several
Calculator 1
Additional masses may be required for
extension work
2.2
2.0
1.8
1.6
1.4
1.2
1.0
Stop
pin
g di
stan
ce, i
n m
0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6x
x
x
x
x
x
x
M ? A
Sample results
Physics TB2 Teachers’ and technicians’ notes 2.2
© Heinemann Educational 2001 37
Distance travelled
down slope in m
Time taken to travel down slope in s Average
speed in
m/s
Speed at
bottom in
m/s
Stopping distance in m
1 2 3 Ave 1 2 3 Ave
0.30 0.78 0.85 0.78 0.80 0.38 0.76 1.02 1.00 1.04 1.02
0.40 0.84 0.91 0.93 0.89 0.45 0.90 1.21 1.23 1.23 1.22
0.50 0.97 1.00 0.97 0.98 0.51 1.02 1.39 1.40 1.41 1.40
0.60 1.12 1.03 1.10 1.08 0.56 1.11 1.60 1.56 1.58 1.58
0.70 1.18 1.19 1.21 1.19 0.59 1.18 1.84 1.80 1.79 1.81
0.80 1.28 1.25 1.31 1.28 0.63 1.25 2.07 2.02 2.00 2.03
0.90 1.37 1.33 1.33 1.34 0.67 1.34 2.18 2.21 2.20 2.20
AM ?
Friction
Aim
This experiment enables students to find the forceneeded to move a block across a board. They thenfind the relationship between the mass of the blockand the frictional force.
Activity procedure1 Students pull a block of wood along across a
wooden board. The force required to pull theblock is found.
2 The block is loaded with weights and the forcerequired to pull it along is found.
3 As an additional activity, the area in contactcould be varied, the surface of the board couldbe changed and a lubricant could be used.
Other resources
Physics Book (pp.22–23)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
For lower ability pupils a table of results and ablank grid with axes labelled and scales couldbe provided.
For more able pupils an investigation could becarried out to find how the area in contactwith the board affects frictional force.
Running the activity
This activity provides good opportunities forpractical activity. The nature of the equipmentused makes repeat readings of little value.
Sample results
Mass of block = 200 g
Total mass in g Friction force in N
200 0.4
400 0.8
600 1.2
800 1.6
1000 2.0
1200 2.4
Material preparation
Wood blocks approximately 15 cm × 10 cm × 2 cmwith a screw eye fitted to one of the smallest faces.The wooden board should be about 50–100 cmlong. Chipboard is a suitable material.
Sample graph
Answers
4 Pulling the block at a steady speed andmeasuring the force accurately with theforcemeter.
5 The area of the block in contact with theboard and the nature of the surfaces.
Physics TB2 Teachers’ and technicians’ notes 2.5
© Heinemann Educational 200138
Materials required per
group
per ( )
groups
Wooden block with screw eye 1
Wooden board 1
0–5 N forcemeter 1
Masses, 10 × 100 g 10
Access to balance
2.5
2.0
1.5
1.0
0.5
0
Fric
tion
for
ce, i
n N
0 200 400 600 800 1000 1200
x
x
x
x
x
x
Mass, in g
M ? A
To investigate a factor which affects thedistance travelled by a projectileAimStudents propel an empty margarine tub across thefloor and measure the distance travelled.
They are able to alter one factor, e.g. distance theelastic band is pulled back. The legs of a laboratorystool are suitable for forming the catapult to launchthe projectile. Slotted masses are used to alter theweight of the projectile.
Activity procedure1 Set the scene with the students and let them
choose a factor to investigate.
Suggested marking criteria
Sc1 matchFull investigation with full Sc1 mark scheme.
Planning available
Obtaining available
Analysing available
Evaluating available
continued
Physics TB2 Teachers’ and technicians’ notes 2.7
© Heinemann Educational 2001 39
Materials required per
group
per ( )
groups
Selection of elastic bands
Forcemeter 0-10 N 1
Margarine tub 1
Slotted masses
Metre rule 1
Sellotape
Skill Area P: PlanningThe mark descriptions are designed to be hierarchical.
Candidates Contextualised mark descriptions
2 marks P.2a Outline a simple procedure Plans to change a suitable factor and measure the distance travelled by a
projectile.
4 marks P.4a Plan to collect evidence which will be
valid
Plans to change the number of elastic bands, or extension of a band, or mass
of the projectile and measure the distance travelled. Refers to controlling all
variables except the one under investigation to ensure a fair test.
P.4b Plan the use of suitable equipment or
sources of evidence
Writes a list of or describes suitable equipment to use, e.g. elastic bands of
similar type and length, metre rule, force meter, projectile and associated
launching equipment such as retort stands or chair legs.
6 marks P.6a Use scientific knowledge and
understanding to plan and
communicate a procedure, to identify
key factors to vary, control or take into
account, and to make a prediction
where appropriate
Uses and communicates clearly scientific knowledge to underpin the plan.
Identifies the factor to vary: a continuous variable such as extension of elastic
band, or mass of projectile.
Identifies explicitly the factors to control for the particular investigation.
Predicts that increasing the extension of the band or decreasing the mass of
the projectile increases the distance travelled because of the increased energy
transferred to the projectile or the lower friction force respectively.
P.6b Decide a suitable extent and range of
evidence to be collected
Plans to use a range of at least five different values of the variable under
investigation to produce significant variations in the distance travelled by the
projectile.
8 marks P.8a Use detailed scientific knowledge and
understanding to plan and
communicate an appropriate strategy,
taking into account the need to produce
precise and reliable evidence, and to
justify a prediction, when one has been
made
Uses and communicates clearly a suitably detailed and quantitative scientific
approach to predict the effect of changing the variable under investigation on
the distance travelled. For example, includes the ideas of potential energy,
kinetic energy, friction and uses equations such as
Energy transferred = (friction) force x distance travelled.
Due to the limited opportunity provided by the procedure to show precision and
skill, recognises the need to use a sampling technique with a large range of
extensions/masses and multiple repeats to ensure reliable data.
P.8b Use relevant information from
preliminary work, where appropriate, to
inform the plan
Performs and reports preliminary practical work to select an appropriate range
of the variable under investigation to give meaningful results.
M ? A
Skill Area O: Obtaining evidence
The mark descriptions are designed to be hierarchical.
Candidates Contextualised mark descriptions
2 marks O.2a Collect some evidence using a simple
and safe procedure
Uses equipment safely and makes a single measurement of the distance
travelled when the number of elastic bands, or the extension of a band, or
mass of the projectile is changed.
4 marks O.4a Collect appropriate evidence which is
adequate for the activity
Uses a suitable range of five values of the extension or mass of projectile to
produce meaningful results of the distance travelled.
O.4b Record the evidence Records the measurements in any format.
6 marks O.6a Collect sufficient systematic and
accurate evidence and repeat or check
where appropriate
Uses a suitable range of five values of the extension or mass of projectile to
produce meaningful results of the distance travelled. Repeats the
measurements so that an average can be determined.
O.6b Record clearly and accurately the
evidence collected
Records results clearly in a tabular format.
Heads columns correctly with appropriate units and records results with
acceptable and consistent number of significant figures.
8 marks O.8a Use a procedure with precision and
skill to obtain and record an
appropriate range of reliable evidence
Recognises that due to the nature of the investigation, measurements of
distance travelled needs to be recorded to the nearest cm only.
Due to the limited opportunity provided by the procedure to show precision
and skill, uses a sampling technique with a large range of extensions/masses
and multiple repeats to ensure reliable data. Differences between repeat
measurements are such as to enable a meaningful average to be calculated.
The accuracy and reliability of the data can be inferred from inspection of the
associated graph
Skill Area A: Analysing and considering evidence
The mark descriptions are designed to be hierarchical.
Candidates: Contextualised mark descriptions
2 marks A.2a State simply what is shown by the
evidence
States simply what has happened, e.g. the further the elastic band was pulled
back the further the projectile travelled.
4 marks A.4a Use simple diagrams, charts or graphs
as a basis for explaining the evidence
Plots a bar chart or simple graph of the distance travelled against extension,
mass or number of elastic bands.
A.4b Identify trends and patterns in the
evidence
Uses the graph, bar chart or data table to identify a trend, e.g. as the mass of
the projectile increases the distance travelled decreases.
6 marks A.6a Construct and use suitable diagrams,
charts, graphs (with lines of best fit,
where appropriate), or use numerical
methods, to process evidence for a
conclusion
Plots a graph of the distance travelled (average values) against mass or
extension. Points are plotted accurately with suitably labelled and scaled axes.
Line of best fit is drawn.
A.6b Draw a conclusion consistent with the
evidence and explain it using scientific
knowledge and understanding
Draws a qualitative conclusion, which refers to the effect of mass or extension
on distance travelled. Explains effect using scientific knowledge and correct
terminology involving terms such as energy, force, and friction. For example,
the heavier the projectile the more friction acts against motion and the less
distance will be travelled.
8 marks A.8a Use detailed scientific knowledge and
understanding to explain a valid
conclusion drawn from processed
evidence
Analyses the graph in a more quantitative way and uses a convincing
quantitative explanation based on suitable equations such as
Energy = (friction) force x distance
A.8b Explain the extent to which the
conclusion supports the prediction, if
one has been made
Compares the results to the original prediction. Clearly tests such predictions as
‘doubling mass halves distance’ by using the data collected from the graph or
plotting distance against 1/mass.
© Heinemann Educational 2001
Physics TB2 Teachers’ and technicians’ notes 2.7
40
M ? A
Skill Area E: Evaluating
The mark descriptions are designed to be hierarchical.
Candidates: Contextualised mark descriptions
2 marks E.2a Make a relevant comment about the
procedure used or the evidence
obtained
Makes any relevant comment about the method used or the data collected.
4 marks E.4a Comment on the quality of the
evidence, identifying any anomalies
Comments on the accuracy of the results
e.g. from inspection of the graph all points were close to the best-fit curve;
due to the nature of the investigation, only appropriate to measure distances
to the nearest +/- 1 cm.
Recognises any anomalous results.
E.4b Comment on the suitability of the
procedure and, where appropriate,
suggest changes to improve it
Comments on the procedure
e.g. projectile rotates/loses contact with the floor during movement; launch
procedure not always consistent; hard to ensure that the projectile always
moved in a straight line
Suggests improvements
e.g. repeat measurements over a greater range of values of extension or
mass; use a clamp system to release the projectile in a standardised way;
use ‘guide lanes’ to ensure linear movement.
6 marks E.6a Consider critically the reliability of the
evidence and whether it is sufficient to
support the conclusion, accounting for
any anomalies
Comments on how close the repeated measurements were to each other
and whether sufficient to support the conclusion.
Refers to multiple sampling technique.
Careful explanation of why rotation/launch procedure can affect distance
travelled and produce anomalous results.
Careful consideration of, for example, the unreliability of measurements
when using low masses.
E.6b Describe, in detail, further work to
provide additional relevant evidence
Depending on the conclusion made, describes in detail further work
e.g. investigate a different surface to see if there is a different quantitative
relationship between distance travelled and extension; use light gates to
measure the times taken to pass particular distances to produce a more
detailed profile of the motion involved.
© Heinemann Educational 2001 41
Physics TB2 Teachers’ and technicians’ notes 2.7
41
M ? A
Measuring reaction time
Aim
This experiment enables students to measure theirreaction time.
Students first check that they can interpret datapresented graphically.
Values obtained for reaction times in this activityare used to calculate ‘thinking distances’ formotor vehicles.
Activity procedure1 Students interpret data presented graphically.2 Students carry out an experiment to measure
their reaction time when a ruler is droppedwithout warning.
3 The values obtained are used to calculate thedistance travelled by a motor vehicletravelling at different speeds while the driverreacts to a hazard.
Other resources
Physics Book (pp.30–31)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
This is a poor task for the assessment of Sc1
Key skills match
Application of number
Communication
ICT
Customising the student sheet
The values in the table for point 4 can be madeharder or easier to handle.
Students could be asked to comment on thereliability of their measurements.
The way of ‘catching’ the rule could be varied.
Running the activity
Students need to be confident that they caninterpret the graph
Answers
distance fallen by
rule (in cm)
time taken (in s)
5 0.10
10 0.14
18 0.19
28 0.23
Speed
(in mph)
Speed
(in m/s)
Distance
travelled (in m)
20 9 1.8 to 2.7
30 13 2.6 to 3.9
50 22 4.4 to 6.6
70 30 6 to 9
Sample results
Typical values for reaction times for this methodare in the range 0.2 to 0.3 seconds.
Physics TB2 Teachers’ and technicians’ notes 2.9
© Heinemann Educational 20014242
Material required per
group
per ( )
groups
Half-metre rule 1
M ? A
Dropping steel ball bearings in oil
Aim
This experiment enables students to discover thatwhen a ball falls in a fluid there is a drag forcewhich opposes the motion of the ball and thateventually the ball reaches a terminal velocity.
Activity procedure
In this investigation the student finds out how thediameter affects the terminal velocity.
Other resources:
Physics Book (pp.32–33)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key Skills match
Application of number
Communication
ICT
Customising the student sheet For less able students, a copy of the table can
be provided.
Running the activityFor more able students, a range of different sizedball bearings could be provided and students coulddevise a method of finding the diameter of eachball. They could also investigate the relationshipbetween terminal velocity and diameter, (terminalvelocity is directly proportional to d2).
For less able students, a table of results could beprovided.
Materials preparationClean motor oil should be used. This should becollected at the end of the experiment and re-used.
Propane 1,2,3triol(glycerol) is a useful alternativeand can be handled safely.
Propane 1,2,3trio(glycerol) is a useful alternativeand can be handled safely.
Answers1 Distance between A and B and between B and
C is 10.0 cm.
Time from
A to B in s
Average
velocity
from A to
B in cm/s
Time from
B to C in s
Average
velocity
from B to
C in cm/s
Large 10.4 10.5
10.7 10.6
10.1 10.0
available
10.4
1.0 Av 10.4 1.0
Small 14.2 15.0
14.6 14.5
14.1 14.1
Av 14.3 0.7 14.5 0.7
2 Shown in the table.3 The time between A and B is the same as the
time between B and C (allowing forexperimental error).
4 The evidence based upon two sizes of ballbearings is not enough. Other sizes of ballbearings should be used.
5 Temperature changes may affect results.Difficulty of accurate timings due to humanreaction times starting and stopping clock.Longer tube would give greater times andreduce errors.Suggest using light gates/sensors to improvetiming.
SafetyAvoid skin contact with motor oil. Use disposablegloves or paper towel/tissue to handle oil-coveredball-bearings. Do not let students pour oil intosinks or drains. Tell them to wash hands after use.
© Heinemann Educational 2001 43
Physics TB2 Teachers’ and technician’s notes 2.10A
Materials required per
group
per ( )
groups
Measuring cylinder (500 cm3) 1
Fresh motor oil 500 cm3
Small elastic bands 3
Two small steel ball bearings (one of
diameter 4 mm and one smaller)
30 cm ruler 1
Stopwatch 1
Magnet 1
Tissues
M ? A
Velocity–time graphs for falling balls
Aim
This experiment enables students to investigatethe behaviour of falling objects by gathering data toplot velocity–time graphs for objects where theratio of gravitational force to resistive forces variessignificantly.
Students have an opportunity to show what theyknow and understand about the effect of forces andterminal velocity.
The data collected can be processed manually or byusing a spreadsheet and a linked graph-plottingpackage.
Activity procedure1 Students allow balls of different weights to fall
under the influence of gravity and resistiveforces.
2 Ticker tape and timers are used to record theposition of the balls at 0.02 s intervals.
3 The separation of the marks produced ismeasured and used to calculate the velocity ofthe balls at 0.02 s intervals allowing graphs ofvelocity against displacement to be plotted andanalysed.
Other resources
Physics Book (pp.32–33, p.4)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Removing references to a ping-pong ballallows students to carry out a complete
investigation on the behaviour of a ping-pongball after practising the procedure with agolf ball.
References to velocity and displacement canbe replaced by speed and distance for lowerability students.
Running the activity
Students should be familiar with the use of tickertimers.
A demonstration of the procedure may be helpful.
If possible, the experiment could be carried out bydropping a large sponge ball down a stair well fortwo storeys.
Sample results
© Heinemann Educational 2001
Physics TB2 Teachers’ and technicians’ notes 2.10B
44
6000
5000
4000
3000
2000
1000
0
Vel
ocit
y in
m/s
0 0.1 0.2 0.3 0.4 0.5 0.6Time in s
2500
2000
1500
1000
500
0
Vel
ocit
y in
m/s
0 0.2 0.4 0.6 0.8 1 1.2
M ? A
What difference does a lid make?
Aim
This experiment enables students to usedatalogging to compare rates of cooling fromvarious types of container under identicalconditions.
Activity procedure1 Students investigate speed of cooling of a
vessel with and without a lid.2 Students work out cooling rates and interpret
their results using computer and dataloggingsoftware.
Other resources
Physics Book (pp.34–35)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Running the activity
Standard 200 cm3 expanded polystyrene cups are verysuitable for this experiment, but some thin plasticcups collapse when very hot water is poured intothem. Alternative cups should be checked by pouringboiling water into a single cup which is in a sink.
Care should be taken because of the scald risk withthe water. Pouring from a kettle is safer thanhaving beakers and Bunsen burners. Cups shouldbe supported, e.g. with a wide clamp, so that theycannot fall over.
It is recommended that two temperature sensorsare used together for swifter comparison, althoughit can be done quite successfully using onesequentially for each vessel. The analysis of coolingrates over given temperature intervals avoids the
need for each to start at the same temperature(which is rarely exact even with two sensors). Thedatalogging can be part of a class practical withsome students carrying out the practical usingthermometers and stopclocks in the usual way. Ifyou have access to an interactive whiteboard orprojection system, students can monitor progresson the large screen at a glance from theirworkstation. This is the best way to present theexperiment as a demonstration if the intent is tofocus on the data analysis aspect of the work.
Students should be given copies of the computergraph output for analysis but may also be able toinput their own data (taken in the normal way withthermometers) so that it can be presented in the sameformat. In this event, they should be encouraged totake temperature readings as frequently as possible toget a large number of data points.
Normally it is sufficient to collect data for 10–15mins but it may be useful to let some experimentscarry on longer to reinforce the point to less ablestudents that the cooling stops when the vesselreaches room temperature and avoid themisconception that it cools to the lowest pointavailable on the graph scale (usually zero).
Data processing
Typically, a lidded cup will cool some two and ahalf to three times slower than an open cupbetween 80 and 75°C so the difference is quiteeasily measurable over a short period of time.Students could look at the possibility of using barcharts to show how the rate of cooling changes asthe temperature range nears room temperature.There is a good opportunity here to extend the useof ICT to include spreadsheets.
© Heinemann Educational 2001
Physics TB2 Teachers’ and technicians’ notes 2.11
45
Materials required per
group
per ( )
groups
250 cm3measuring cylinder 1
Waterproof marker 1
Polystyrene cups and a lid 2
Access to kettle for hot water
Temperature sensors and interface 2
Computer and datalogging software
Access to other cups, metal calorimeters
and vacuum flasks (for extension work)
M ? A
Reflection of light by a plane mirror
Aim
This experiment enables students to investigatethe behaviour of a ray of light when it is reflectedby a plane mirror.
Students are able to draw conclusions from theirobservations and comment on the reliability of theevidence gathered.
Extension material allows students to beintroduced to the use of plane mirrors in aperiscope.
Activity procedure1 Students shine rays of light onto a plane
mirror and draw the path of the rays on paper.2 Angles of incidence and reflection can be
measured and compared.
Other resources
Physics Book (pp.50–51)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Point 6 in the ‘what to do’ section can bechanged to remove reference to either plasticor glass mirrors.
The number of angles to be used can be varied.
Extension work can be removed.
Running the activity
A means of providing partial blackout will beneeded.
Either plastic mirrors cut from a large sheet orsmall plane mirrors can be used.
Bulldog clips can be used as an alternative tocommercially available mirror holders.
Sample results
angle i angle r
23° 24°
32° 31°
46° 46°
57° 55°
68° 70°
79° 81°
Physics TB3 Teachers’ and technicians’ notes 3.4
© Heinemann Educational 200146
Materials required per
group
per ( )
groups
Plane mirror 1
Mirror holder 1
Ray box 1
Single slit 1
Power supply 1
Protractor 1
Plain paper 1
Pencil 1
M ? A
Refraction of light by a perspex block
Aim
This experiment enables students to investigatethe behaviour of a ray of light when it passesthrough a perspex block.
Students are able to draw conclusions from theirobservations and comment on the reliability of theevidence gathered.
As an extension, students could complete Activity3.5B and use a spreadsheet to investigate therelationship between i and r.
Activity procedure1 Students shine rays of light onto a perspex
block and draw the path of the rays on paper.2 Angles of incidence and refraction can be
measured and compared.
Other resources
Physics Book (pp.52–53)Customisable worksheet on CD-ROM
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Running the activity
A means of providing partial blackout will beneeded.
Sample results
angle i angle r
10° 7.5°
20° 15.0°
40° 29.5°
50° 36.0°
60° 41.5°
70° 46.5°
Physics TB3 Teachers’ and technicians’ notes 3.5A
© Heinemann Educational 2001 47
Materials required per
group
per ( )
groups
Perspex block 1
Ray box 1
Single slit 1
Power supply 1
Protractor 1
Plain paper 1
Pencil and ruler 1
M ? A
How does the angle change?
AimThis experiment enables students to collect anglesof incidence and refraction for a number of lightrays and then use a spreadsheet to find the bestmathematical relationship between them.
Activity procedure1 Students measure angles of incidence and
refraction using a raybox and glass block.2 Students use a spreadsheet to find a relation-
ship between angles of incidence and refraction.
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Running the activityGlass or plastic blocks are equally suitable. It maybe useful to have the centre of the flat side markedwith a small gap in black tape or marker pen toimprove the narrowness of the beam (see diagram).
Safety
Do not knock glass blocks against each other. Bitsof glass may fly off.
A B C D E F G H
1 Angle (i) Angle (r) TAN (i) TAN (r) SIN (i) SIN (r) COS (i) COS (r)
2 10 7.7 =TAN (A2
*PI()/180)
=TAN (B2
*PI()/180)
=SIN (A2
*PI()/180)
=SIN (B2
*PI()/180)
=COS (A2
*PI()/180)
=COS (B2
*PI()/180)
The ray box should have as narrow a slit as possibleto improve accuracy, students should beencouraged to use very sharp pencils for themarking out and try to achieve a reading accuracyof half a degree from the protractor.
Although a minimum of six values of incidenceangle are suggested (10° intervals) it is reasonable toexpect most students to do more (e.g. 5° intervals)
Spreadsheet work
Students should have had some previousexperience with spreadsheets.
It is advisable to prepare a suitable spreadsheet readyfor students to access. For the weakest students, theheadings and functions could be in place as shownfor the common spreadsheet EXCEL. The functionsshown in row 2 need to be copied down the columnfor enough rows to accommodate the likely datasets. Similarly, the number of decimal places shouldbe specified in advance.
More able students could be left to insert their ownheadings and functions starting with a basictemplate to insert angle data.
Discussion may be needed to establish the bestrelationship (Snell’s sine ratio) and use ofcorrelation functions could be examined.
The exercise can be purely data-handling ifstudents are supplied with information formaterials of different refractive indices.
Physics TB3 Teachers’ and technicians’ notes 3.5B
© Heinemann Educational 200148
Approx 1 cmblacked-out
Centre left clear
Materials required per
group
per ( )
groups
Glass or plastic semi-circular block 1
Sheet of A3 paper 1
Raybox with narrow slit 1
Protractor 1
Ruler 1
Sharp pencil 1
Access to computer with spreadsheet
package such as EXCEL
M ? A
Answers
1–3Having worked out a relationship, studentscould be encouraged to continue to use thespreadsheet to look at the effect of errors. Forexample, what difference does it make to theslope of the line (proportionality constant/refractive index) if there is a 1° error in readingthe angles of refraction? Students could add (orsubtract) 1° from each angle (r) and replot.
4 Students could research the significance ofhigh refractive index lenses (thinner for thesame correction power), for example, by usingweb sites for high street opticians.
Refraction data
The following can be used as source data for aninvestigation of the refractive index of unknownmaterials.
This might be used for Analysis.
Material A: Refractive Index 1.3
Angle of incidence ° 10 15 20 25 30 35 40 45 50 55 60 65 70
Angle of refraction ° 7.5 11.5 15.0 19.0 22.5 26.0 29.5 33.0 36.0 39.0 41.5 44.0 46.5
Material B: Refractive Index 1.5
Angle of incidence ° 10 15 20 25 30 35 40 45 50 55 60 65 70
Angle of refraction ° 6.5 10.0 13.0 16.5 19.5 22.5 25.5 28.0 30.5 33.0 35.0 37.0 38.5
Material C: Refractive Index 1.7
Angle of incidence ° 10 15 20 25 30 35 40 45 50 55 60 65 70
Angle of refraction ° 6.0 8.5 11.5 14.5 17.0 19.5 22.0 24.5 27.0 29.0 30.5 32.0 33.5
Physics TB3 Teachers’ and technicians’ notes 3.5B
© Heinemann Educational 2001 49
M ? A
The visible spectrum
Aim
This experiment enables students to determinethat the speed of electromagnetic waves changeswhen they pass from one material into another andthat this is called refraction.
Students discover that the change in speed mayresult in a change in direction and that the amountby which the direction changes depends on thewavelength and frequency of the waves.
Activity procedure:1 Students direct a narrow beam of white light
from a source on to one face of an isoscelestriangular prism and place a vertical whitescreen in a suitable position to detect the lightthat leaves the opposite face of the prism.
2 Students adjust the position of the prism toobtain the best spectrum and then observe andrecord the appearance of the spectrum.
Other resources
Physics Book (pp.62–63)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match:
Application of number
Communication
ICT
Customising the student sheet
High achievers should use an LDR connectedto a resistance meter to detect theelectromagnetic radiation within and eitherside of the visible spectrum. They should usesecondary sources to identify the radiations
detected beyond the red and blue parts of thevisible spectrum.
Questions 4 and 5 should be removed for lowachievers as they will not understand thewavelengths and frequencies given in standardindex form.
Running the activity
Students need to be shown how to position theprism and the screen. They need to be remindedhow to connect the white light source to the powersupply and of the correct voltage setting.
Answers5 red, orange, yellow, green, turquoise (cyan),
blue.6 blue7 At the faces of the prism.
1 The speed decreases.2 blue3 red4 decreases5(i) red5(ii)blue6 The longer the wavelength, the smaller the
change in speed.
Physics TB4 Teachers’ and technicians’ notes 4.1
© Heinemann Educational 200150
Materials required per
group
per ( )
groups
Power supply 1
12 V 24 W lamp in holder 1
Slit to produce a narrow beam 1
Isosceles prism 1
White screen which will stand vertically 1
M ? A
Where do the earthquakes happen?
Aim
This exercise enables students to search and gatherdata off the internet from a variety of sites and touse this data in an ICT context to construct asuitable presentation.
Key skills match
Application of number
Communication
ICT
Running the activity
Once students are clear about the task, in theinterests of efficient time management it is worthletting them spend a few minutes choosing suitablesearch phrases before releasing them onto theinternet. Linked phrases such as ‘earthquakestatistics uk’ are usually good enough to narrowdown the search and get to a relevant web site.
The various seismic organisations are highlyinterlinked so that once one is found, otherrelevant ones are easily to hand. Photographs ofearthquake damage can be found on some sites, butif there has been a recent big earthquake, televisionnews sites are a good source of visual material.Unless funds are unlimited, it is advisable to setground rules about what can be printed and when itshould be done. Many students are happy to carryon the activity at home.
Some useful sites to get you started
Site Comment
www.neic.cr.usgs.gov/neis US national earthquake information centre
quake.geo.berkeley.edu/cnss Berkeley Institute data bank
www.gsrg.nmh.ac.uk UK National Seismological Archive
www.iris.washington.edu Incorporated Research Institute for Seismology
vcourseware5.calstatela.edu Simulation to locate quakes and calculate magnitude
www.ceri.memphis.edu Centre for earthquake research and information
seismo.ethz.ch/seismosurf Extensive lists and links
www.geo.ed.ac.uk/quakes/quakes.html Edinburgh University earthquake locator
You may wish to split the task between differentgroups of students and co-ordinate their work in adisplay. One strategy might be to split the worldinto different areas and get each group to report onwhat has been happening in their area. Anothermight be to let one group of students prepare adaily report which is published on a convenientnoticeboard. Students often suggest their ownvariations, so be prepared to be flexible as to theoutcomes. Some American sites will allow you toset up a search which can be left on the server forabout a week, constantly being updated. Some sitesalso provide simulations for students to workthrough. Although not always relevant to the task,they can be useful in reinforcing importantconcepts.
Physics TB4 Teachers’ and technicians’ notes 4.6–4.8
© Heinemann Educational 2001 51
ICT required per group
Computer with:
– internet connection– word processor– spreadsheet– desktop publisher– presentation package, e.g. Powerpoint– access to colour printer
M ? A
Absorption of radioactivity: Teacherdemonstration
Aim
This experiment enables students to observe thatradioactive emissions occur when unstable nucleichange to a more stable state.
They will discover that there are three main typesof radioactive emission, known as alpha, beta andgamma and that these radiations are distinguishedin terms of their penetration and their ability tocause ionisation.
Students will discover that there is backgroundradiation from the ground, the atmosphere, thefood that we eat, buildings and medical andindustrial uses of radioactive materials.
Activity procedure1 Demonstrate the existence of background
radiation and obtain a value for the averagebackground count. Relate backgroundradiation to the various sources responsible.
2 Using an alpha source, students measure andrecord the total count in one minute using:(a) no absorber; (b) a 5 cm air gap as absorber;and (c) a 3 mm thickness of aluminium as anabsorber.
3 Using a beta source, students measure andrecord the total count in one minute using:(a) no absorber; (b) a 5 cm air gap as absorber;(c) a 3 mm thickness of aluminium as anabsorber; and (d) a 2 mm thickness of lead asan absorber.
4 Using a gamma source, students measure andrecord the total count in one minute using:(a) no absorber; (b) a 5 cm air gap as absorber;(c) a 3 mm thickness of aluminium as anabsorber; (d) a 2 mm thickness of lead as anabsorber; and (e) a 2 cm thickness of lead as anabsorber.
Other resources
Physics Book (pp.86–87)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Safety
Do not allow students access to any source. Checkfor possible theft.
Teachers should observe the following points:
1 Do not handle any radioactive materialsdirectly: always use tongs or a source handlingtool.
2 Do not point radioactive materials at anyperson, i.e. the metal gauze end of a sealedsource.
3 No student should be closer than 2 m toradioactive materials.
4 The radioactive sources should only beremoved from the secure store when they areneeded and returned to that store as soon asthe experiments are completed.
Key skills match
Application of number
Communication
Customising the student sheet
Removing the outline table of results willmake it useful for Sc1 Obtaining Evidenceskill.
High achievers should take sufficientmeasurements to enable them to plot a graphof count rate against thickness for thealuminium absorber. They can use the graphto estimate the thickness of aluminiumrequired to reduce the count rate by one half.
Low achievers should compare thecomparative dangers to users of radioactivematerials in terms of the penetration powersonly.
Physics TB5 Teachers’ and technicians’ notes 5.2
© Heinemann Educational 200152
Materials required
for demonstration
Alpha, beta and gamma sources andsuitable holder
Tongs for handling the sources Detector, e.g. Geiger-Müller tube counter A range of thicknesses of aluminium foil
and lead
M ? A
Running the activity
Teachers who have been trained to teach secondaryscience are qualified to work with these sealedsources. However, if the teacher is unfamiliar withthe activity there must be in-house trainingorganised by the head of department utilising thosewho do have the appropriate skills. Where studentsare under 16 years of age the activity must only bea teacher demonstration.
Answers
1 Alpha, it had the greatest count rate.2 Alpha.3 The radiation is totally absorbed by a small air
gap, so it would not penetrate the plasticcasing of a smoke alarm.
4 Yes – even though the count rate with a 5 cmair gap may be slightly higher than with noabsorber, the difference is accounted for by therandom variability in background radiation.
5 The radiation spreads out as it leaves the sources,so less enters the window of the G-M tube.
6 Any two from: stay at least 2 m away from a radioactive
material
never handle a radioactive materialdirectly, always use tongs
do not point a radioactive source towardsany person.
Sample results
source absorber number of counts in 1 minute
background radiation none 42
alpha none 325
5 cm air 44
3 mm aluminium 39
beta none 255
5 cm air 126
3 mm aluminium 41
2 mm lead 44
gamma none 164
5 cm air 84
3 mm aluminium 66
2 mm lead 62
2 cm lead 51
Physics TB5 Teachers’ and technicians’ notes 5.2
© Heinemann Educational 2001 53
M ? A
Simulation of radioactive decay
Aim
This experiment teaches students that radioactivedecay is a random process and that decay of anindividual nucleus cannot be predicted.
Using a random number generator studentssimulate radioactive decay and find a half-life.
Activity procedure1 Students generate random numbers from a
computer.2 Students process the numbers and find a
half-life.3 Students discover that large numbers are
required to get a valid half-life.
Other resources
Physics Book (pp.88–89)
Sci match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet:
For able students no help needs to be given.
For less able students a copy of a blank tableand a grid with axes and scales could beprovided.
Running the activity
A number of groups of students are able to use asingle computer. They go to the computer togenerate numbers and then move away to processthem.
This activity could be carried out with a largenumber of cubes with one face painted. After eachthrow every cube with the painted face pointingupwards is removed. The remaining cubes arethrown again.
Using a random number generator speeds up theprocess. It also enables different groups to havedifferent number ranges, e.g. 1–6, 1–7, 1–8 etc. thisgenerates different ‘half-lives’.
Materials preparation
A number of random number generatorprogrammes can be downloaded from the Internet.One example is http://segobit.virtalave.net/rng.htm.
The alternative method uses a large number ofcubes with one face painted.
Sample results
Number generated Number of throws
240 0
196 1
173 2
131 3
115 4
101 5
84 6
67 7
55 8
43 9
39 10
33 11
28 12
Physics TB5 Teachers’ and technicians’ notes 5.3
© Heinemann Educational 200154
Materials required per
group
per ( )
groups
computer 1
random number generator programme 1
access to printer
or
small cubes with one face painted 240
M ? A
Answers
2 Place the material close to a Geiger-Mullertube connected to a counter or ratemeter orcomputer interface. Record the reading atintervals.
3 It is a curve with a decreasing slope orgradient.
4 Depends on students results. Using sampleresults the half-life is about four throws.
5 Greater precision can be achieved by using alarger number of random numbers at the start.
Physics TB5 Teachers’ and technicians’ notes 5.3
© Heinemann Educational 2001 55
250
200
150
100
50
0
Nu
mbe
r of
un
deca
yed
cube
s
0 2 4 6 8 10 12
Number of throws
M ? A
Use of a van de Graaff generator to linkelectric charge and current: Teacherdemonstration
Aim
In this experiment students will learn that a flowof electric charge is an electric current and that thegreater the rate of flow of charge, the greater theelectric current.
They will discover that the rate of flow of chargecan be increased by putting the charged platescloser together and that the rate of flow of chargecan be decreased by putting the charged platesfurther apart.
Activity procedure1 Arrange the apparatus as shown in the
diagram.2 Connect the dome of the van de Graaff
generator to one of the metal plates.3 Connect the other plate to the galvanometer
and then to the earth connection on the van deGraaff generator.
4 Switch on the van de Graaff generator.5 Observe the motion of the ping-pong ball.6 Observe the galvanometer.7 Repeat for different plate separations.
Other resources
Physics Book (pp.118–119)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Answers
1 The ping-pong ball carries charge from oneplate to the other, completing the circuit. This
means that charge flows around the circuitand a current is indicated by the galvanometer.
2 + + –3 When the ball touches the positive plate it
becomes positively charged. Like charges repelso it moves away and is attracted towards thenegative plate.On touching the negative plate the ball gainselectrons and becomes negatively charged.Like charges repel so the ball now movestowards the positive plate and the process isrepeated.
4 (a) moves faster(b) increases
5 (a) When there is a smaller distance betweenthe plates the forces of attraction arestronger so the ball moves more quickly.
(b) Since the ball moves faster charge istransferred more rapidly from one plate tothe other – the rate of flow of charge isgreater. Current is equal to the rate offlow of charge so the current increases.
Physics TB7 Teachers’ and technicians’ notes 7.3
© Heinemann Educational 200156
Materials required fordemonstration
van de Graaff generator Two metal plates Ping-pong ball coated in graphite or conducting
paint, suspended by a nylon thread from awooden clamp stand
Sensitive galvanometer such as an Edspot Connecting leadsAll the above to be connected as shown in thediagram on the Student Sheet.
Safety
1 High voltage. Discuss the dangers andprecautions necessary.
2 Do not touch the apparatus once the van deGraaff generator is switched on.
3 Check that the dome and plates are notcharged before touching the apparatus at theend of the experiment.
4 Keep students at a distance of 1.5–2.0 m.
M ? A
How fast does the motor go?
AimIn this experiment students find that the speed of amotor using data from a light sensor and correlatethis with electrical readings using a spreadsheet.
Activity procedure1 Students obtain data from a light sensor.2 Students calculate the speed of a motor and
plot this against current, voltage and powerconsumption.
3 The values obtained are analysed.
Other resourcesPhysics Book (pp.132–138)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Running the activityThe motor should be thetype which has aremovable flywheel, suchas one from a Meccanokit. Lego motors may alsobe suitable. The flywheelneeds to have a slit which is fairly narrow in order toproduce fine spikes on the trace.
Current and voltage sensors could replace theammeter and voltmeter, but as these should notchange during a run, there is little to be gained byusing them.
If the light sensor needs calibrating, set it to zerowith the power off and 100% with the power on.A 6 V or 12 V torch bulb is adequate for the lightunit. The presence of cardboard tubes on the sensorand the light unit will cut out ambient light andgive clearer results, but the experiment can becarried out without them in place.
Students should start at the minimum voltagewhich will get the motor turning and use this todecide suitable increments up to the maximumrating. If there is not a continuously variable powersupply available, a suitable rheostat placed in serieswith the motor will give an adequate voltage range.
To investigate the effect ofload, the easiest way is tochange the type of flywheel.Identical diameter flywheelsmade from card, plastic, woodand different metals can beused. Alternatively, lead foilcan be attached symmetricallyto add weight but keepthe wheel balanced.
Students may suggestthat the motor isturned and used toraise known loads ina vertical plane. Thisis feasible providedthe motor will accepta suitable spindle.
Variations
If there is a gearbox available for the motor, studentscould look at the speed related to gear ratio and load.
Motors from different sources, e.g. model trainsand racing cars could be compared.
Safety
High speed spinning discs are an obvious hazard.Warn students of this.
Physics TB8 Teachers’ and technicians’ notes 8.2
© Heinemann Educational 2001 57
Flywheel Slit
Motor
Lead foil
Materials required per
group
per ( )
groups
Computer with datalogging software and
interface
1
Printer 1
Light sensor and light unit 1
Ammeter 1
Voltmeter 1
Variable power supply 1
Electric motor fitted with flywheel 1
Suitable leads 1
Access to a spreadsheet such as Excel
Lightunit
Motor
Sensor
Weights
M ? A
How does voltage depend on speed?Teacher’s guide
Aim
This experiment enables students to observe theform of the induced emf in a coil as a magnet fallspast it, and to use datalogging to measure the speedof the magnet and relate it to the emf.
Activity procedure1 Students obtain data for variation in induced
voltage with speed of a moving magnet.2 Students analyse results and display them
graphically (with possible use of Excelspreadsheet).
Other resources
Physics Book (pp.134–135)
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Running the activity
This experiment affords a useful example of usingtwo sensors in parallel and using the power of thecomputer software to process the data. It may bethat the datalogging software is capable ofdisplaying derived speed values against inducedvoltages, so avoiding the need to use asupplementary spreadsheet program such as‘Excel’. Some students will need to be givenspecific instructions as to how to achieve this, butmore able ones could be allowed to do their ownprogram setting.
A satisfactory coil can be made from 250–300 turnsof 28 swg enamelled copper wire wound in anarrow pattern around a former, manufactured
from a cardboard tube of appropriate diameter forthe guide tube being used. Connections can bemade simply with 4 mm plugs. If the unit ismounted into a small plastic box, it will be moredurable. Coils from demountable transformers mayalso be suitable as they have the advantage of highnumbers of turns but the disadvantage of havingsquare central holes which may not fit the guidetube. Cylindrical magnets about 2 cm long aresuitable, and the stronger they are the better. If thevoltage sensor is not capable of reading negativevoltages, one solution is to offset the voltage usingthe coil as part of a potential divider as shown.
The experiments are quick to do and manyrepetitions are possible within a normal lessonspan. One possible strategy is to allow all studentsto take turns in small groups and pool the data.Students could deliberately accelerate the magnetdown the tube instead of letting it fall undergravity in order to obtain a larger range of speeds.
If light gates are not available, an alternative is tovary the drop height. The magnet will beaccelerated to different speeds but they will not beknown. An estimate could be obtained usingstandard motion equations, otherwise induced emfcan be related simply to the height.
Physics TB8 Teachers’ and technicians’ notes 8.3
© Heinemann Educational 200158
Coil
Resistor(100R)
OV To voltage sensor
+V To voltage sensor
+SV
Materials required per
group
per ( )
groups
Computer with appropriate datalogging
software and interface
Voltage sensor
Pair of light gates
Coil unit(s) – see below
Guide tube: glass or plastic 1.5m long,
30mm diameter
Small cylindrical magnet
Foam rubber
M ? A
Electromagnetic induction
Aim
This experiment teaches students that a voltage isinduced when the magnetic field through a conductorchanges and that an induced current passes when avoltage is induced in a complete circuit.
Students learn that the size of the induced voltagedepends on the rate at which the magnetic fieldchanges and that reversing the change of the magneticfield reverses the direction of the induced voltage.
Activity procedure1 Students wind a coil of 2–3 cm diameter and
15–20 turns, this is connected to a sensitiveammeter which can detect currents in eitherdirection.
2 Students compare the ammeter deflectionwhen:
the N pole of a strong bar magnet is movedslowly towards one end of the coil
the N pole of the magnet is moved quicklytowards the same end of the coil
the magnet is held stationary inside the coil
the S pole of the magnet is moved towards thesame end of the coil.
3 Students then wind two separate coils of15–20 turns onto iron c-cores; one coil (theprimary) is connected to a 1.5V cell through aswitch. The other coil is connected to asensitive ammeter.
4 Students compare the ammeter deflectionwhen:
the current in the primary coil is switched on
the current in the primary coil remains on
the current in the primary coil is switched off.
Other resources
Physics Book (pp.136–137).
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Removing the outline table of results will make ituseful for Sc1 Obtaining Evidence skill.
High achievers should estimate and record the sizeof the induced currents.
Low achievers will benefit from having the effectsdemonstrated using a many-turn coil and adatalogger to record the induced voltage.
Running the activity
Students need to be made aware that they areobserving very small induced currents. They mayneed to be shown how to zero the ammeter so thatpositive and negative current values are readilyobserved. It should be emphasised that all the turnson each coil of wire should be wound in the samedirection.
continued
Physics TB8 Teachers’ and technicians’ notes 8.4
© Heinemann Educational 2001 59
Materials required per
group
per ( )
groups
1 metre length of single strand wire 2
Sensitive ammeter 1
Strong bar magnet 1
One pair of c-cores 1
1.5 V d.c. cell in holder 1
Switch 1
Connecting leads and crocodile clips as
necessary
Wire cutters/strippers 1
M ? A
Sample results
Action Ammeter indication
N pole moved slowly towards
coil
small positive pulse of current
N pole moved rapidly towards
coil
larger positive pulse of current
Magnet held stationary inside
coil
no current
S pole moved towards coil negative pulse of current
Current in primary coil
switched on
positive pulse of current
Current in primary coil remains
on
no current
Current in primary coil
switched off
negative pulse of current
Answers
1 The faster the speed of movement, the greaterthe reading on the ammeter.
2 Reverse the direction of movement of themagnet; reverse the polarity of the magnet(reversing the connections to the coil or thedirection of winding the coil are alsoacceptable answers).
3 The magnetic field through the coil is notchanging.
4 The primary coil becomes an electromagnet,its changing magnetic field passes through thesecondary coil.
5 As there is a steady current passing, themagnetic field in the secondary coil is notchanging.
6 The magnetic field is now collapsing ratherthan growing, so the change in the magneticfield is opposite to when the current isswitched on.
7 An alternating current.
Physics TB8 Teachers’ and technicians’ notes 8.4
© Heinemann Educational 200160 60
M ? A
Transforming the voltage
AimThis experiment will demonstrate to students thata voltage is induced in a conductor when themagnetic field through it changes.
Students will discover that a transformer consists oftwo separate coils of wire wound on an iron coreand that a changing current in one coil (the primary)produces a changing magnetic field in the other coil(the secondary), causing an induced voltage.
Students will learn that a transformer can changethe size of an alternating voltage.
Activity procedure1 Students wind two separate 15- turn coils of
wire onto c-cores.2 One coil (the secondary) is connected to a
lamp, the brightness of which gives anindication of the size of the induced voltage.
3 Students connect a d.c. source to the primarycoil and note that the lamp does not light.They then replace this with a low voltage a.c.source and use the brightness of the lamp as areference for future experiments.
4 Students then change the numbers of turns ofwire on the secondary coil and note thebrightness of the lamp.
Other resourcesPhysics Book (pp.138–139).
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the pupil sheet Removing the outline table of results will make
it useful for Sc1 Obtaining Evidence skill.
High achievers could predict and investigatethe effect of changing the numbers of turns onthe primary coil, while keeping the number ofturns on the secondary coil the same.
For low achievers, the action of thetransformer with both a d.c. input and an a.c.input should first be demonstrated.
Running the activity
It is important that normal laboratory powersupplies are not used as they could be damaged.If students join wires by twisting together the baredends, the joins must be insulated with tape andstudents must be warned never to use thisprocedure with mains electricity.
Sample results
Input
(primary)
voltage
Number of
primary
turns
Number of
secondary
turns
Lamp brightness
(off, dim, normal
or bright)
1.5 V d.c. 15 15 off
2.0 V a.c. 15 15 normal
2.0 V a.c. 15 10 dim
2.0 V a.c. 15 20 slightly brighter than
normal
2.0 V a.c. 15 25 bright
2.0 V a.c. 15 30 very bright
Answers
2 The magnetic field does not change when asteady current passes. There is only a momentarychange when the current is switched on.
3 The magnetic field through the secondary coilis continually changing.
4 There are fewer turns on the secondary thanon the primary.
5 There are more turns on the secondary than onthe primary.
6 (a) step-up. (b) step-down.
Physics TB8 Teachers’ and technicians’ notes 8.5
© Heinemann Educational 2001 61
Materials required per
group
per ( )
groups
2-metre lengths of single strand insulated
wire
2
Westminster power pack 1
Iron c-cores 2
2.5 V lamp in holder 1
Screwdriver
Wire cutters/strippers
M ? A
Logic circuits using AND, OR and NOT gates
Aim
Students will learn how to set up logic circuitsusing AND, OR and NOT gates and how to verifythe output signal for various inputs.
Activity procedure1 Students set up logic circuits and complete
truth tables.2 Students discover that an AND gate gives a
high (logic 1) output only when both inputsare high, an OR gate gives a high output wheneither or both the inputs are high, and a NOTgate acts as an inverter.
3 Students draw up truth tables to summarisethe behaviour of a logic gate.
4 Higher Tier students show that a NAND gateinverts the output of an AND gate and a NORgate inverts the output of an OR gate.
Other resourcesPhysics Book (pp.148–157)Manual provided by manufacturer of electronicsequipment.
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheetThis may need to be adapted depending on theelectronics system available.
SafetyHazards are minimal with LV supply but studentsusing incorrect power settings may ‘blow’components.
If in doubt the teacher should check a student’scircuit before switching on the power supply.
Answers
1 AND gate truth table 0 0 0 1OR gate truth table 0 1 1 1NOT gate truth table 1 0 (for (i) and (ii))
2(b) Suggested practical applications:AND(i) To operate a washing machine or spin
dryer only if the door is shut.(ii) To open a greenhouse window if it is hot
during the day.OR(i) To switch on the internal light in a car if
either driver’s or passenger’s door is open.(ii) To switch on the central heating boiler if
the thermostat in the living room orkitchen falls below a certain temperature.
NOTto reverse the output of a sensor to givethe required response; e.g. so that theoutput of a light sensor becomes high inthe dark and so a light is switched on.
2(c) Truth tables will depend on the combinationsof logic gates selected.
(H) level1 Truth table for both is 1 1 1 02 Truth table for both is 1 0 0 0
© Heinemann Educational 2001
Physics TBA1 Teachers’ and technicians’ notes A1.1–A1.3
62
Materials required per
group
per ( )
groups
Low voltage (5 V) power supply
AND, OR and NOT gates – at least one of
each
Minimum of two input sensors, chosen from
light, temperature, moisture sensors
Suitable output, such as LED, lamp, buzzer
connecting leads
(H) NAND and NOR gates – at least one of
each
Extra gates and input sensors will be
required if some students go on to combine
logic gates
Note Teachers may wish to customise the pupil sheet to suit the
electronics system available.
M ? A
Measuring specific heat capacity
Aim
This experiment teaches students that the energyrequired to raise the temperature of 1 kg ofmaterial by 1°C or 1 K is called the specific heatcapacity and is measured in J/kgK or J/kg °C.
Students learn that the energy transfer fromelectricity to a circuit component is calculated usingenergy transfer = current × voltage × time = IVt.
Activity procedure1 Students record the initial temperature of a
1kg metal block.2 Students switch on the immersion heater until
the temperature has risen by about 10°C andrecord the current, voltage and time for whichthe heater is switched on.
3 Students record the maximum temperaturereached after the heater has been switched off– not the temperature when the heater isswitched off.
4 The procedure is repeated for other metals.
Other resources
Physics Book (p 198–199).
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet
Removing the outline table of results willmake it useful for Sc1 Obtaining Evidence.
High achievers should investigate therelationship between the energy required and
the number of atoms in 1 kg of material forthe metals which are elements.
For low achievers, the activity can besimplified by using a joulemeter to measurethe energy input – but note that these metersrequire the use of an alternating voltagesupply.
Running the activity
A heat-resistant mat should be used underneaththe metal blocks. If time is short, different groupscan experiment with the different metal blocks andpool results. Emphasise the dangers of handling theheaters – there is no way of telling whether aheater is hot or cold.
Groups of students may share metal blocks.
Safety
The heaters can burn the skin if allowed to get toohot. When not in use, they should be left inside theblocks or placed on a heat-resistant mat.
Beware of mercury from a broken thermometerbeing left inside the hole in the block, with thebroken glass.
Answers
1 It is large enough to be measured without toomuch uncertainty and it is small enough tominimise energy losses to the surroundings.
2 The metal block heats the surrounding air;this energy is then removed by convectioncurrents.
continued
Physics TBA3 Teachers’ and technicians’ notes A3.6
© Heinemann Educational 2001 63
Materials required per
group
per ( )
groups
1 kg blocks of aluminium, iron, brass and
copper
Stopwatch 1
Standard laboratory thermometer 1
12 V power supply 1
0–5 A ammeter 1
0–15 V voltmeter 1
12 V, 24 W immersion heater 1
M ? A
3 By covering the metal block with insulatingmaterial.
4 The measured value is higher than the actualvalue since more energy is needed to heat theblock and replace the energy lost.
5 1 kg of different metals contains differentnumbers of atoms.
Sample results
These results were obtained using 1 kg metalblocks and a 24 W heater.
Material initial temp.
in °C
final temp.
in °C
current
in A
voltage
in V
time
in s
specific heat capacity
= (current voltage × time)
÷ (1 kg × temperature rise)
brass 18 29 2.0 12.0 175 382
iron 21 30 2.0 12.0 180 480
copper 19 31 2.0 12.0 200 400
aluminium 22 33 2.0 12.0 405 884
Physics TBA3 Teachers’ and technicians’ notes A3.6
© Heinemann Educational 200164
M ? A
Efficiency of a ramp
AimThis experiment teaches students that the workdone in moving an object is calculated usingwork = force × distance moved.
Students calculate the gravitational potentialenergy gained when an object is raised verticallyusing weight × vertical height.
Students find that the efficiency of a machine isthe fraction of the energy input that becomesuseful energy output, efficiency = useful energyoutput ÷ total energy input.
Activity procedure1 Students measure the energy input needed to
raise a load by lifting it vertically and bydragging it up a slope.
2 Students calculate the efficiency of a ramp andinvestigate how the efficiency changes withincreasing steepness of the slope.
Other resourcesPhysics Book (pp.200–201).
Sc1 match
Planning Not available
Obtaining available
Analysing available
Evaluating available
Key skills match
Application of number
Communication
ICT
Customising the student sheet Removing the outline table of results will
make it useful for Sc1 Obtaining Evidence.
High achievers should use the results to plot agraph of efficiency against height of slope.
For low achievers, the activity can be simplifiedby completing the first two blank columns ofthe table (using the sample results).
Running the activityEach group requires a large amount of space.Depending on the space available, this may dictatethe number of students in each group.
Material preparationThe materials used for this activity are very similarto those for Activity 2.4 on Friction.
Answers2 Dragging the mass up the slope.3 Work has to be done against friction.4 The same amount whether it is lifted or
dragged.5 Dragging enables a smaller force to be used.6 More work has to be done.7 The steeper the slope, the greater the
efficiency.
Sample resultsThese results were obtained using a distance,
s = 0.80 m.
Physics TBA3 Teachers’ and technicians’ notes A3.7
© Heinemann Educational 2001 65
Materials required per
group
per ( )
groups
Wooden board approximately 1 m long 1
1 kg mass 1
Metre rule 1
0–10 N forcemeter 1
Wooden blocks for raising one end of the
board
Height of ramp,
h in m
Force needed to lift
mass vertically
h in N
Work done in lifting
mass vertically in J
Force to drag mass
through distance s
up slope in N
Work done in
dragging mass up
slope in J
Efficiency = work in
lifting mass ÷ work in
dragging mass
0.10 9.8 0.98 4.4 3.52 0.28
0.20 9.8 1.96 5.3 4.24 0.46
0.30 9.8 2.94 5.9 4.72 0.63
0.40 9.8 3.92 6.6 5.28 0.74
0.50 9.8 4.90 7.3 5.84 0.84
M ? A
Using Topic help
The Heinemann/OCR Physics book is written for a wide range of student ability. Topic help isintended to provide additional help for students with particular learning difficulties.
Students have such a wide range of learning difficulties. Topic help is provided on paper andCD-ROM so that the teacher can tailor help for the particular difficulties of individual studentsor groups of students.
Many students find difficulty understanding and using scientific vocabulary. Throughout thebook, key words have been identified for each double-page spread. Each of these words is definedin the Glossary. Topic help tries to confirm the correct meaning and use of these words. If thiscan be done, it should make the book more accessible.
Each Topic help page supports one double-page spread in the book,provided that the double page has key words. The learning page is dividedinto four parts.
1 A list of Key words for the double-page spread.
2 A brief definition of each of the Key words. Students could matcheach of the definitions with the Key words. This could be done byindividual students or could be done with a group using an overheadprojector.
3 The Key words are repeated, but sometimes other useful words areadded. These might help in answering the questions in 4.
4 A series of questions that help to use the Key words in the correct context.
The teacher can adapt these questions by removing unwanted questions, adding other questions,or providing more or less information.
© Heinemann Educational 2001
Physics Topic help Introduction
66
1 2
3 4
M ?
Electric circuits1 You need this to do work.
2 A flow of electric charge.
3 It reduces the current in a circuit.
4 It changes resistance when light shines on it.
5 It changes resistance when warmed.
6 Use this to change the resistance in a circuit.
7 It only allows current in one direction.
8 A very small negative particle.
9 It shines when a current passes through it.
Electric circuits
1 What do these circuit symbols represent?
(a) _______________________________________
(b) _______________________________________
(c) _______________________________________
(d) _______________________________________
(e) _______________________________________
(f) _______________________________________
2 Draw on the circuit diagram, an arrow to show the direction of thecurrent.
© Heinemann Educational 2001 67
Physics TB1 Topic help 1.1A
Physics TB1 Topic help 1.1B
current diode electron energy light dependent
resistor light emitting
diode resistance thermistor variable resistor
current diode electron energy light dependent
resistor light emitting
diode resistance thermistor variable resistor
M ? T
Electric circuits1 A meter used to measure voltage is called a
2 Electric current is measured in units called
3 When current divides to pass through two resistors, the resistorsare in
4 Voltage is measured in units called
5 A meter used to measure current is called an
Electric circuits
1 What do these circuit symbols represent?
(a) _______________________________________
(b) _______________________________________
2 Add the correct letter to the meter symbols. Write in the boxes.
3 Finish the sentences.
(a) A voltmeter is connected in ___________________ with aresistor.
(b) An ammeter is connected in ___________________ with aresistor.
© Heinemann Educational 2001
Physics TB1 Topic help 1.2A
68
ammeter ampere parallel volt voltmeter
Physics TB1 Topic help 1.2B ammeter ampere current parallel series volt voltage voltmeter
A
V
M ? T
Electric circuits1 A material which is not a very good conductor but is not an
insulator either.
2 A very small unit of electric current.
3 A material which obeys Ohm’s Law is
Electric circuits
1 What is the symbol for milliamp? ___________________
2 How many milliamps are there in one amp? ___________________
3 Put a ring around the material which is a semiconductor.
copper
iron
plastic
rubber
silicon4 Put a ring around the graph which shows the behaviour of an
ohmic material.
© Heinemann Educational 2001 69
Physics TB1 Topic help 1.3A
Physics TB1 Topic help 1.3B
milliamp ohmic semiconductor
milliamp ohmic semiconductor
V
I
V
I
V
I
V
I
M ? T
Forces and energy1 The turning effect of a force.
2 Two equal and opposite turning forces are called a
3 The turning effect of two equal and opposite forces.
4 The place where a lever balances is called a
5 Moment is measured in units called
6 A balanced lever is in
Forces and energy1 For each see-saw, write down which side (left or right) goes up or if
it is balanced.
___________________________________
___________________________________
___________________________________
2 Finish the sentence.A screwdriver can help remove the lid of a paint tin easier than a 10pcoin. This is because the screwdriver has more ___________________ .
© Heinemann Educational 2001
Physics TB2 Topic help 2.1A
70
couple equilibrium moment newton metre pivot torque
Physics TB2 Topic help 2.1B
couple equilibrium leverage moment newton metre pivot torque
400 N
1.5 m 2.0 m
500 N
400 N
1.5 m 2.0 m
300 N
400 N
2.5 m 2.0 m
500 N
M ? T
Forces and energy
How fast something is moving.
Steepness of a graph.
A line drawn to touch, but not cross, a curve is called a
Forces and energy
1 Look carefully at these graphs. Theyshow how five bodies moved.
(a) Which body was moving forthe longest time?___________________
(b) Which body was moving thefastest? ___________________
(c) Which two bodies moved thesame distance ___________________ and ___________________
(d) Which body started at a different place to all of the others?___________________
(e) Which body was moving the slowest? ___________________
2 A car travels 90 km in 1½ hours. What is its average speed in km/h?
___________________ km/h
3 The diagrams show some lengths oftickertape. A dot is put on the tapeevery 1/50 second.
(a) Which tape was changing speedas the dots were put on the tape?___________________
(b) Which tape was moving the slowest but at a constant speed?___________________
© Heinemann Educational 2001 71
Physics TB2 Topic help 2.2A
Physics TB2 Topic help 2.2B
gradient speed tangent
gradient speed tangent
Dis
tan
ce
A B
C
D
E
Time
A
B
C
M ? T
Forces and energy
How fast something is moving in a straight line.
Something which has a size and a direction.
Something which has a size but no direction.
Distance moved in a straight line.
Forces and energy
1 A car travels in a straight line between two points 1000 m apart. Ittakes 40 s to travel the distance. What is the average velocity of thecar? ___________________ m/s
2 Speed is a scalar. Put rings around two other scalars in this list.
displacementmasstemperaturevelocity
3 Look at this displacement–time for a car journey.
Put rings around the statements which correctly describe the carjourney.
The car finished its journey at the same place as it started.The car was never travelling at a constant velocity.The car was stationary at position C.The car was not stationary at position D.
© Heinemann Educational 2001
Physics TB2 Topic help 2.3A
72
displacement scalar vector velocity
Physics TB2 Topic help 2.3B
displacement scalar vector velocity
Dis
plac
emen
t
M ? T
Forces and energy1 These two words mean the same.
___________________ and ___________________
2 Getting faster.
3 Attraction between the Earth and all objects on the Earth.
Forces and energy
1 Look carefully at these graphs. They show how five bodies movedduring a certain length of time.
(a) Which body was travelling at a constant velocity?___________________
(b) Which body was slowing down? ___________________
(c) Which two bodies started at rest? ___________________ and___________________
(d) Which body had the largest acceleration? ___________________
(e) Which body was moving the slowest at the end of the period oftime? ___________________
2 A stone falls from the top of a cliff onto the the beach below. Itaccelerates at 10 m/s2.
(a) What is its velocity one second after it starts to fall?___________________ m/s
(b) What force caused it to fall? ___________________
3 A car is travelling at 100 km/h. A dog runs into the road in front ofthe car. The car slows down.
Finish the sentences.
When the car slows down its v___________________ gets smaller.
This is known as d___________________.
© Heinemann Educational 2001 73
Physics TB2 Topic help 2.4A
Physics TB2 Topic help 2.4B
acceleration deceleration gravity retardation
acceleration deceleration gravity retardation
Vel
ocit
y
D
E
C
Time
B
A
M ? T
Forces and energy1 A pull or push of one object on another.
2 The force in a stretched spring.
3 A slowing down force as something moves through the air.
4 A contact force between two sliding objects.
5 Upward force on an aircraft wing, for example.
6 Force on an object acting vertically downwards.
7 A force from a rocket engine, for example.
8 A force which opposes motion through a liquid or gas.
Forces and energy
1 What type of force causes each of the following?
(a) A hot air balloon to rise. ___________________
(b) A ball rolling across grass to stop. ___________________
(c) A tile to fall from a roof. ___________________
(d) A diver to slow down on entering water. ___________________
(e) A catapult elastic to spring back. ___________________
2 The helicopter has four forces acting on it. Name them.
F1 ___________________
F2 ___________________
F3 ___________________
F4 ___________________
© Heinemann Educational 2001
Physics TB2 Topic help 2.5A
74 74
Physics TB2 Topic help 2.5B
air resistance drag force friction gravity lift tension thrust weight
air resistance drag force friction lift tension thrust weight
M ? T
Forces and energy1 The total force acting on a body.
2 Two or more forces which cancel out.
3 Forces which do not cancel out.
4 A shape which cuts down drag forces.
Forces and energy
1 The pictures show helicopters with forces acting on them.The length of the arrows indicates the size of the force. Answertrue or false to each statement about how each helicopter moves.
(a) Up and forwards ___________________________
(b) Up only ___________________________
(c) Down and back ___________________________
(d) Hovering still ___________________________
2 Put a ring around the shape which will fall fastest through water.
© Heinemann Educational 2001 75
Physics TB2 Topic help 2.6A
balanced resultant streamlined unbalanced
Physics TB2 Topic help 2.6B
balanced resultant streamlined unbalanced
sphere cube cone
M ? T
Forces and energy1 Energy is measured in units called
2 Weight is measured in units called
3 Power is measured in units called
4 What is done when a force is moved through a distance.
5 The rate at which a force is moved through a distance.
6 Energy of a body because of its position above the ground.
7 Energy of a body because of its velocity.
Forces and energy
1 Units are often named after famous scientists.
These have names which are the same as the units for work, forceand power.
Who were the scientists?
___________________ ___________________ ___________________
2 A golf ball on a crazy golf hole goes up and down mounds on itsway to the hole. It takes this path.
(a) Where does the ball have most kinetic energy?
___________________
(b) Where does the ball have most gravitational potential energy?
___________________
(c) Where does the ball have least gravitational potential energy?
___________________
(d) Where does the ball not change gravitational potential energy?
___________________
© Heinemann Educational 2001
Physics TB2 Topic help 2.8A
76
Physics TB2 Topic help 2.8B
gravitationalenergy
potential energy joule kinetic newton power watt work
gravitationalpotential
joule kinetic newton power watt work
M ? T
Forces and energy1 How long does it take for the brain to respond to a signal?
2 How far does a car travel while the brain is responding to a signal?
3 How far does a car travel from when the driver puts his foot on thebrake to when the car stops?
4 The total distance travelled by a car before it stops.
Forces and energy
1 The Highway Code states thinking, braking and stopping distancesat different speeds.
(a) At 20 miles per hour, John’s thinking distance is 7 m and his
braking distance 8 m. What is his stopping distance?
___________________
(b) At 30 miles per hour, is his thinking distance less than 7 m,
7 m or more than 7 m? ___________________
(c) At 60 miles per hour, the stopping distance stated in the
Highway Code is 74 m. How would this distance change if the
road was wet? ___________________
2 Put rings around the things which might affect a person’s thinkingdistance.
age of driver
amount of alcohol drunk by driver
make of car
state of brakes
outside temperature3 Put rings around the things which might affect a person’s braking
distance.
age of driver
amount of alcohol drunk by driver
road surface
state of brakes
time of day
© Heinemann Educational 2001 77
Physics TB2 Topic help 2.9A
braking distance reaction time stopping distance thinking distance
Physics TB2 Topic help 2.9B
braking distance reaction time stopping distance thinking distance
M ? T
Forces and energy1 The force which acts on falling objects.
2 The fastest a falling object can go.
3 A slowing down force as something moves through the air.
Forces and energy
1 A sky-diver jumps out of a plane and falls to Earth. She reaches hermaximum velocity. She then opens her parachute. Does hervelocity increase, decrease or stay the same?
2 The diagram shows a ball falling through syrup. Its position isshown at half-second intervals. Where did it reach its terminalvelocity?
3 In which direction does air resistance act on afalling body?
© Heinemann Educational 2001
Physics TB2 Topic help 2.10A
78
Physics TB2 Topic help 2.10B
air resistance gravity terminal velocity
air resistance gravity terminal velocity
M ? T
Forces and energy1 Thermal energy is transferred through liquids by
2 Thermal energy is transferred through solids by
3 Thermal energy is transferred through space by
4 A poor conductor
5 It allows work to be done more easily.
6 The time it takes to recover money spent on insulating a home.
Forces and energy
1 (a) Which thermal energy transfer
process is taking place in the
water? ___________________
(b) In which direction does the cork
move? ___________________
2 (a) Which thermal energy transfer
process is taking place from the
flame to the hand through the rod?
___________________
(b) What type of material could be used for
a handle to stop the person being
burned? ___________________
3 Which thermal energy transfer process is taking
place from the potato? ___________________
© Heinemann Educational 2001 79
Physics TB2 Topic help 2.11, 2.12A
conduction convection insulator machine pay back period radiation
Physics TB2 Topic help 2.11, 2.12B
conduction convection insulator pay back period radiation
cork
M ? T
Wave properties1 A wave family which includes light.
2 A wave whose displacement is in the same direction as its motion.
3 A wave whose displacement is at right angles to its direction ofmotion.
4 The to and fro motion of a particle.
5 Area of a wave where particles are closer together than normal.
6 Area of a wave where particles are further apart than normal.
Wave properties
1 Put rings around the waves which are not electromagnetic waves.
infrared sound
radio ultraviolet
water X-rays2 Write the letter R at the centre of a rarefaction and the letter C at
the centre of a compression.
3 Use a double headed arrow (←→ ) to show the direction ofdisplacement of particles in the transverse wave.
4 Use a double headed arrow (←→ ) to show the direction ofdisplacement of particles in the longitudinal wave.
© Heinemann Educational 2001
Physics TB3 Topic help 3.1A
80
Physics TB3 Topic help 3.1B
compression electromagnetic
wave longitudinal wave rarefaction transverse wave vibration
compression electromagnetic
wave longitudinal wave rarefaction transverse wave vibration
M ? T
Wave properties1 Frequency is measured in units called
2 The distance between two points of similar displacement.
3 The maximum displacement of a wave from its rest position.
4 The number of complete waves passing a point each second.
5 The rate of change of distance with time.
6 The rate of change of distance with time in a straight line.
Wave properties
1 This is a transverse wave.
(a) What does the distance x represent? ___________________
(b) What does the distance y represent? ___________________
2 This is a longitudinal wave.
What does the distance z represent? ___________________
3 A duck on a lake bobs up and down on the waves 10 times in
20 seconds. What is the frequency of the waves?
___________________
© Heinemann Educational 2001 81
Physics TB3 Topic help 3.2A
amplitude frequency hertz speed velocity wavelength
Physics TB3 Topic help 3.2B
amplitude frequency hertz speed velocity wavelength x
y
M ? T
Wave properties1 The point at which waves converge.
2 A surface which curves inwards.
3 A surface which curves outwards.
4 Wave paths getting closer together.
5 Wave paths getting further apart.
6 The position of a wave at a given point in time.
7 A flat or straight surface.
8 A single wave.
9 Scientific apparatus used to study water waves.
10 Instrument which makes waves appear to be still.
Wave properties
1 The arrows show the directions of water waves.
(a) What is the shape of the surface
which caused the wave pattern?
___________________
(b) Mark the focus with an X.
(c) Finish the missing word. The wavesd_ _ _ _ _ _ from the focus.
2 A wave pulse is made in a ripple tankby dropping a small piece of rubber into the water. Draw the shapeof the wavefront.
© Heinemann Educational 2001
Physics TB3 Topic help 3.3A
82
Physics TB3 Topic help 3.3B
concave converge convex diverge focus plane pulse ripple tank stroboscope wavefront
concave converge convex diverge focus plane pulse ripple tank stroboscope wavefront
surface
Small piece
of rubber
Ripple
tank
M ? T
Wave properties1 A line drawn at 90° to a surface. ___________________
2 A ray travelling towards a mirror. ___________________
3 A ray travelling away from a mirror.
4 The angle between a ray and a mirror.
5 Scattered reflection. ___________________
6 Reflection of sound. ___________________________________________
7 Repeated reflection of sound.
8 The change in direction of a wave at a boundary.
Wave properties
1 Light is reflected from a mirror.
(a) Write the letter N on the normal.
(b) Write the letter I on the incident ray.
(c) Write the letter R on the reflected ray.
(d) Write the letter G in the glancing angle.
2 A ray of light is travelling towards a glass block.
(a) Write the letter N on the normal.
(b) Continue the path of the ray into the glass block.
(c) What is happening to the light as it passes into the glass?
Use a word from the list. ___________________
© Heinemann Educational 2001 83
Physics TB3 Topic help 3.4, 3.5A
diffuse echo glancing angle incident ray normal reflected ray refraction reverberation
Physics TB3 Topic help 3.4, 3.5B
diffuse echo glancing angle incident ray normal reflected ray refraction reverberation
glassblock
M ? T
Wave properties1 A reproduction of an object formed by a lens or mirror.
2 It can be projected onto a screen.
3 It only appears to be there.
4 The spreading out of a wave after it passes through a gap.
5 The distance of an object below the surface.
6 Where the object appears to be below the surface.
7 When an object and image are lined up together.
Wave properties
1 Put rings around the images which are real.
image formed by a plane mirror
image formed by a pinhole camera
image formed by a convex mirror
image formed by an overhead projector2 A fisherman is watching a fish.
(a) Mark and label on thediagram the real depth ofthe fish.
(b) Mark and label on thediagram the apparent depthof the fish.
3 Joe uses a voltmeter. There is amirror under the scale. His teacher tells him that this will help Joeto read the pointer accurately. He moves his head until he findsno-parallax. Where is the image of the pointer?
Put a ring around the correct answer.
to the left of the pointer behind the pointer
to the right of the pointer
© Heinemann Educational 2001
Physics TB3 Topic help 3.6, 3.7A
84
Physics TB3 Topic help 3.6, 3.7B
apparent depth diffraction image no-parallax real depth real image virtual image
apparent depth diffraction image no-parallax real depth real image virtual image
M ? T
Using waves1 The cause of a suntan.
2 Radiation from a warm body.
3 Used for examining broken bones.
4 Energy sources arranged in order of wavelength.
5 A light-emitting substance.
6 Waves used for communication.
7 Type of wave to which our eyes are sensitive.
Using waves
1 Which colour in the visible spectrum is next to infrared?
2 Put rings around the colours which are not colours in the visiblespectrum.
red yellow
pink green
orange purple
blue3 Radio waves are used to send messages long distances. What other
type of wave is used for sending messages long distances?
4 What is the speed of all electromagnetic waves in air?
5 Police officers often wear special jackets to make them morevisible. This is particularly true at night. What type of material isthe jacket made from? F______________________________________
6 Which part of the television set in your home fluoresces?
© Heinemann Educational 2001 85
Physics TB4 Topic help 4.1A
fluorescent infrared radio spectrum ultraviolet visible light X-rays
Physics TB4 Topic help 4.1B
fluorescent infrared radio spectrum ultraviolet visible light X-rays
M ? T
Using waves1 An electronic device whose resistance changes with temperature.
2 A picture formed by recording different temperatures.
Using waves
1 How can you tell, just by looking, that a coal fire is hotter than anelectric iron?
2 Which part of the electromagnetic spectrum makes us feel hotwhen the sun shines?
3 Which part of the electromagnetic spectrum gives us a tan whenthe sun shines?
4 Put a ring around the things which work because of infraredradiation.
electric bar fire
fluorescent lighting
night sights
remote control for hi-fi unit
security marking of personal property5 One day in June, the normal burn time in the sun is 15 minutes.
Draw a line from each time that a person wants to spend in theSun, to the correct minimum sun screen factor.
factor 2
four hours
factor 5
one hour
factor 10
three hours
factor 15
two hours
factor 20
© Heinemann Educational 2001
Physics TB4 Topic help 4.2A
86
Physics TB4 Topic help 4.2B
thermistor thermograph
thermistor thermograph
M ? T
Using waves1 Device used to receive or transmit radio signals.
2 A body orbiting Earth.
3 Electromagnetic radiation given out in radioactive decay.
4 High-energy electromagnetic radiation capable of penetrating skinbut not bone.
5 Communication waveband in the electromagnetic spectrum.
6 Electromagnetic waves used for cooking.
7 The use of reflected radio waves to measure distance.
8 Part of the upper atmosphere, capable of reflecting some radio waves.
Using waves
1 Draw a line from each wave box to the correct wavelength box.
2 mm
long wave radio
2 m
medium wave radio
200 m
microwave
2 km
short wave radio
200 km
2 All luggage is scanned at airport baggage handling centres.What type of electromagnetic wave is used to scan the luggage?
© Heinemann Educational 2001 87
Physics TB4 Topic help 4.3A
aerial gamma ray ionosphere microwave radar radio satellite X-rays
Physics TB4 Topic help 4.3B
M ? T
Using waves1 Device used to look inside the body.
2 Very small diameter length of glass along which light passes.
3 Regular shaped block of glass.
4 The behaviour of light in a dense material if the angle of incidenceis too large.
5 A series of pulses which may be either on or off.
6 An angle of incidence which produces an angle of refraction of 90°.
Using waves
1 Put rings around the digital signals.
2 A ray of light is travelling towards a glass block.
(a) Angle A is 45°. What happens at I?
(b) Finished the diagram to show the path of the ray.
(c) Finish labelling the diagram.
3 What is used in an endoscope to transmit the light into the patientand the reflected light back to the eyepiece?
O___________________ f___________________
© Heinemann Educational 2001
Physics TB4 Topic help 4.4A
88
Physics TB4 Topic help 4.4B
critical angle digital signal endoscope normal optical fibre prism total internal
reflection
critical angle digital signal endoscope optical fibre prism total internal
reflection
np
I
A
a of
i
M ? T
Using waves1 High-frequency sound, beyond the range of human hearing.
2 The use of sound waves to measure distance or aid navigation.
Using waves
1 Which three animalsnavigate byecholocation?
Put rings around theright answers.
2 A boat searcheswhilst it is at sea.What could it locateusing sonar?Underline the rightanswers.
aircraftoverhead
other boats
sea bed
shoal of fish
submarine
sunkenwreck
© Heinemann Educational 2001 89
Physics TB4 Topic help 4.5A
sonar ultrasound
Physics TB4 Topic help 4.5B
echolocation sonar ultrasound
Bat
Dog
Elephant Rat
Cat
Dolphin
M ? T
Using waves1 Molten rock below the surface.
2 Molten material from a volcano extruded onto the Earth’s surface.
3 Rock blasted out from a volcano.
4 The centre of the Earth.
5 The outer layer of the Earth.
6 The major part of the Earth, between the centre and outer layer.
7 The outer part of the mantle and lower part of the crust.
8 Theory which explains the movement of continents over longperiods of time.
Using waves
1 Finish labelling the diagram of the structure of the Earth.
2 The figure shows a volcano erupting. Label the lava and thevolcanic ash.
© Heinemann Educational 2001
Physics TB4 Topic help 4.7A
90
Physics TB4 Topic help 4.7B
continental drift core crust lava lithosphere magma mantle volcanic ash
continental drift core crust lava lithosphere magma mantle volcanic ash
c
m
c
M ? T
Using waves1 A layer of floating mantle.
2 Change of state of rock due to pressure and heat.
3 A section of the Earth’s crust.
4 The moving apart of plates and the formation of new crust bymagma from the mantle.
5 The border between plates where new lithosphere is formed as theplates separate.
6 The border between plates where lithosphere is destroyed as theplates collide.
7 Area where an oceanic plate goes below a continental plate.
8 Formed when one plate moves up and over another.
Using waves
1 What does this diagram show? Choose your answer from the list onthe left.
2 Many volcanoes are found at plate boundaries. What other eventsoften happen at plate boundaries?
© Heinemann Educational 2001 91
Physics TB4 Topic help 4.8A
asthenosphere constructive
boundary destructive
boundary metamorphism plate sea-floor spreading subduction zone trench
Physics TB4 Topic help 4.8B
asthenosphere constructive
boundary destructive
boundary metamorphism plate sea-floor spreading subduction zone trench
LithosphereOceanic crust
Asthenosphere
Rising magma
M ? T
Radioactivity1 The nucleus of a helium atom.
2 A high speed electron.
3 Penetrating electromagnetic radiation.
4 Atom of an element with a different mass number.
5 A radioactive atom.
6 A particle formed when a neutron changes to a proton and a beta particle.
7 The number of protons in an atom.
8 The number of protons plus neutrons in an atom.
9 Everyday radiation which is always around us.
Radioactivity
1 The diagrams show the nuclei of some atoms. For each atom, writedown the atomic number and the mass number.
2 A radioactive isotope decays and forms an isotope of an elementone place higher in the periodic table.
(a) What type of radiation is emitted? ___________________
(b) How does the mass compare? ___________________
3 A radioactive isotope decays and forms an isotope of an elementtwo places lower in the periodic table.
(a) What type of radiation is emitted? ___________________
(b) How does the mass compare? ___________________
4 A radiation detector shows a reading even when there are noradioactive sources in the room. Why?
© Heinemann Educational 2001
Physics TB5 Topic help 5.1A
92
Physics TB5 Topic help 5.1B
alpha particle antineutrino atomic number background
radiation beta particle gamma ray isotope mass number radioisotope
alpha particle antineutrino atomic number background
radiation beta particle gamma ray isotope mass number radioisotope
(a)
Key: neutron proton
(b)
M ? T
Radioactivity1 Detector of alpha radiation which relies on air being ionised.
2 Worn by people who use radiation to measure their exposure to theradiation.
3 Detector of beta and gamma radiation which relies on argon beingionised.
4 The addition or removal of electrons from an atom.
5 Energy which travels as rays, waves or particles.
Radioactivity
1 Which type of radiation, alpha, beta or gamma, is the mostionising?
2 Which type of radiation, alpha, beta or gamma, will pass throughthick lead sheets?
3 Which type of radiation, alpha, beta or gamma, has a range of about1 m in air?
4 Which type of radiation, alpha, beta or gamma, travels at the samespeed as light?
5 Why is it not possible to detect beta and gamma radiation with aspark counter? Put a ring around the correct answer.
They travel too large a distance.
They are too penetrating.
They do not ionise air enough.
They have the wrong charge.6 The diagram shows the film from Peter’s
film badge after it has been developed.The film goes black if it has been exposedto radiation.
The black area is where the film is notcovered by any plastic or metal. What typeof radiation alpha, beta or gamma has Peterbeen mainly exposed to? ___________________
© Heinemann Educational 2001 93
Physics TB5 Topic help 5.2A
film badge Geiger-Müller
tube ionisation radiation spark counter
Physics TB5 Topic help 5.2B
film badge Geiger-Müller
tube ionisation radiation spark counter
M ? T
Radioactivity
The splitting of an isotope with the emission of radioactivity.
An isotope which emits radiation and changes to an isotope of adifferent element.
An isotope which is formed as a result of the splitting of anotherisotope.
The time it takes for half the nuclei in a radioactive material to decay.
The rate at which a radioactive source is decaying.
A unit of radioactivity equal to one decay each second.
Radioactivity
1 The graph shows how a radioactive sample decays during a 12 hourperiod.
What is the half-life of the radioactive sample? ___________________
2 Radium-226 decays and emits an alpha particle to form radon-222.
(a) Which is the parent nuclide? ___________________
(b) Which is the daughter nuclide? ___________________
3 A radioactive sample is decaying. It emits 6000 alpha particles each
minute. Write down its activity in becquerels. ___________________
© Heinemann Educational 2001
Physics TB5 Topic help 5.3A
94
Physics TB5 Topic help 5.3B
activity becquerel daughter nuclide decay half-life parent nuclide
activity becquerel daughter nuclide decay half-life parent nuclide
1000
750
Activityin counts
per minute500
250
00 2 4 6
Time in hours
8 10 12
M ? T
Radioactivity1 Simple organisms which may cause disease. _____________________
2 Tumours which grow out of control. ____________________________
A process for destroying organisms. _____________________________
The technique used for estimating the age of the Turin Shroud.
A radioisotope introduced into a system which allows itsmovement through the system to be monitored.
Radioactivity
1 Which type of radiation is used to sterilise the scissors used by
surgeons in hospital? ___________________________________________
2 Which type of radiation is used to treat skin cancer? ______________
3 Which type of radiation is used to treat a brain tumour? ___________
4 Which type of radiation is used in a smoke alarm? ________________
5 Which type of radiation is used in a smoke alarm? ________________
6 The half-lives of some carbon isotopes are listed.
carbon-10 19.255 secondscarbon-11 20.39 minutescarbon-14 5730 yearscarbon-15 2.449 secondscarbon-16 0.747 seconds
Which isotope is used for radiocarbon dating? _____________
7 Americium-241 is used in smoke alarms. Which properties make it
a good radioisotope to use? Put a ring around the correct answer.
emits alpha radiation and has a short half-life
emits alpha radiation and has a long half-life
emits gamma radiation and has a short half-life
emits gamma radiation and has a long half-life
© Heinemann Educational 2001 95
Physics TB5 Topic help 5.4, 5.5A
bacteria cancer radiocarbon dating sterilisation tracer
Physics TB5 Topic help 5.4, 5.5B
alpha radiation beta radiation bacteria cancer gamma radiation radiocarbon dating sterilisation tracer
M ? T
Radioactivity1 Illness caused by exposure to radioactivity.
2 Damage to the skin caused by exposure to radioactivity.
3 A molecule which contains coded genetic information.
4 A type of white blood cell.
5 Alterations in genetic material which change the cell.
6 Increasing by repeated addition.
Radioactivity
1 What do the initials DNA stand for? Put a ring around the correctanswer.
deoxyribonucleic acid
di-nitrogen acid
dual nuclear additive2 Young people have to be a certain age before they are allowed to
handle radioactive material. At what agecan they handle radioactive material?
_____________
3 Three ways in which we protect ourselvesfrom radioactivity are by using shielding,distance and time of exposure.
Which way is being used when radioactivematerial is taken by lorry in large flasks?
_______________________________________________________________
4 What does this symbol mean?
__________________________________________
© Heinemann Educational 200196
Physics TB5 Topic help 5.6A
96
cumulative DNA lymphocyte mutation radiation burns radiation sickness
Physics TB5 Topic help 5.6B
cumulative DNA lymphocyte mutation radiation burns radiation sickness
M ? T
The Earth and Universe1 Force acting towards the centre of a circle which keeps a body
moving in a circle.
2 Force of attraction between two bodies.
3 Any small body in orbit around a larger body.
4 A large body in orbit about a star.
5 A small rock in orbit around the Sun, between Mars and Jupiter.
6 A small lump of ice and dust orbiting the Sun in a very elongatedelliptical orbit.
7 The part of the Universe which contains the Sun and everythingwhich is circling around it.
8 A satellite orbit which passes over the North and South Poles.
A satellite orbit above the equator which takes 24 hours to circlethe Earth.
The Earth and Universe
1 The diagram shows a satellite, S, orbiting Earth, E. Draw an arrowon the diagram to show the direction of the force acting on thesatellite.
2 A communications satellite takes 24 hours to orbit the Earth.A weather satellite takes only 2 hours. Put a ring around thereason why.
The weather satellite is in polar orbit.
The weather satellite is closer to the Earth.
The weather satellite orbits in the opposite direction.
© Heinemann Educational 2001 97
Physics TB6 Topic help 6.1A
Physics TB6 Topic help 6.1B
asteroid centripetal comet geo-stationary
orbit gravity planet polar orbit satellite Solar System
asteroid centripetal comet geo-stationary
orbit gravity planet polar orbit satellite Solar System
E
S
M ? T
The Earth and Universe1 An area of space, so dense that not even light can escape.
2 The joining together of light nuclei with the release of energy.
3 A newly formed star.
4 A small star whose fuel has run out.
5 A small, dense collapsed star.
6 An average sized star which expands at the end of its life.
7 A large star with a short life.
8 A faded white dwarf.
9 Clouds of dust and gas.
10 The explosion of a star at the end of its life.
The Earth and Universe
1 The Sun contains isotopes of an element which fuse together andrelease energy.
(a) The isotopes from which element fuse together? _____________
(b) Which element is formed by the fusion process? _____________
2 A protostar is formed when clouds of gas and dust are drawntogether. What type of force draws the gas and dust together?Put a ring around the correct answer.
electrostatic gravity magnetic3 Arrange the following in order of size starting with the smallest.
red giant red supergiant white dwarf
___________________ ___________________ ___________________
4 Which star has the longest life – a small star or a large star?
© Heinemann Educational 2001
Physics TB6 Topic help 6.2A
98
black dwarf black hole blue supergiant nebulae neutron star nuclear fusion protostar red giant supernova white dwarf
Physics TB6 Topic help 6.2B
black dwarf black hole blue supergiant nebulae neutron star nuclear fusion protostar red giant supernova white dwarf
M ? T
The Earth and Universe1 Probably the brightest object in the Universe.
2 The explosion which scientists believe started the expansion of theUniverse.
3 The possible collapse of the Universe.
4 A visible effect when a galaxy is moving away.
5 The difference in frequency caused by a moving body.
The Earth and Universe
1 Put a ring around what was present at the time of the Big Bang.
galaxies nothingplanets stars
2 The diagram shows the positions of four galaxies relative to Earth.
Which galaxy shows the greatest amount of red shift?_____________
3 Light from quasars takes about 12 billion years to reach Earth. Put atick next to the statement which is most likely to be true.
The age of the Universe is less than 12 billion years.
The age of the Universe is about 12 billion years.
The age of the Universe is more than 12 billion years.4 Light from a nearby galaxy appears bluer than expected. Finish the
sentences.
The name of this effect is b_____________ shift. It means that the
galaxy is moving t_____________ us.
5 Bobbie is listening to the siren on an ambulance. The pitch isincreasing. Is the ambulance moving towards or away from Bobbie?
_____________
© Heinemann Educational 2001 99
Physics TB6 Topic help 6.3A
Physics TB6 Topic help 6.3B
Big Bang Big Crunch Doppler effect quasar red shift
Big Bang Big Crunch Doppler effect quasar red shift
E
Earth G1 G2 G3 G4
(not to scale)
M ? T
Using electricity1 A positively charged particle.
2 A neutral particle.
3 A negatively charged particle.
4 The central region of an atom.
5 The flow in an electric circuit.
6 A material which has low resistance.
7 A material which does not allow an electric current to pass through it.
8 A device which uses electrostatics to produce high voltages.
9 The result of two similar charges close together.
10 The force between two surfaces rubbing together.
Using electricity
1 When two surfaces rub together they may become charged.One surface gains electrons and the other loses electrons.
(a) What is the charge on the surface which gains electrons?
(b) What is the charge on the surface which loses electrons?
2 Why is an atom neutral (uncharged)? Put a ring around the correctanswer.
Atoms contain only neutrons.
Atoms have the same number of protons as electrons.
Atoms are conductors and lose charge.3 Two charged spheres attract. The charge on one of the spheres is
positive. What is the charge on the other? _____________
4 Finish the sentence.
A negatively charged balloon sticks to a wall. The wall has become
positively charged by i_____________
© Heinemann Educational 2001
Physics TB7 Topic help 7.1A
100
charge conductor electron friction insulator neutron nucleus proton repel van de Graaff
generator
Physics TB7 Topic help 7.1B
charge conductor electron friction induction insulator neutron nucleus proton repel van de Graaff
generator
M ? T
Using electricity1 Powdered ink. _________________________________________________
2 Electrostatic device which is used to duplicate a document.
3 Electrostatic device which is used to reduce pollution from factory
chimneys. ____________________________________________________
4A chemical which is non reactive. ______________________________
5A chemical which is burned to release energy. ___________________
6A high-voltage spark from a cloud. ______________________________
Using electricity1 A precipitator in a factory chimney has negatively charged wires.
As the smoke goes up the chimney the same charge is put on thedust particles. The dust particles are attracted to large metal platesand stay on them.
(a) What is the charge on the dust particles after they have passed
the wires? _____________
(b) What is the charge on the large metal plates? _____________
2 When aircraft are refuelled, friction can cause the fuel to becomecharged. The aircraft and the tanker are joined by a cable. Put a ringaround the correct statement.
The cable is a good conductor to prevent a build-up of charge.
The cable is a poor conductor to allow the charge to leak slowly.
The cable is an insulator to make sure the charge cannot pass.3 Finish the sentences.
Air is normally an i_____________. If there is a large voltage
difference air can become a c_____________. The voltage differencebetween a thundercloud and the Earth may be many thousands of
volts. A spark from a cloud to Earth is called _____________.
4 Liquid fertiliser in a crop sprayer becomes charged as it flowsthrough the pipes. Which diagram, A, B or C shows how the spraycomes out of the nozzle? ____
© Heinemann Educational 2001 101
Physics TB7 Topic help 7.2A
101
Physics TB7 Topic help 7.2B
fuel inert lightning photocopier precipitator toner
fuel inert lightning photocopier precipitator toner
A B C
M ? T
Using electricity1 Charge is measured in units called
2 A small negatively charged particle.
3 An atom which has gained or lost negative charge.
4 The flow in an electric circuit.
5 The opposite direction to the flow of electrons in an electric circuit.
Using electricity
1 The diagram shows a simple circuit.
(a) Draw on the diagram an arrow to show the direction ofconventional current. Label this arrow X.
(b) Draw on the diagram an arrow to show the direction of flow ofcharge. Label this arrow Z.
2 A current from a battery is passed through asolution of salt water. The salt water containspositive and negative ions.
Which type of ion moves towards the positiveterminal of the battery?
© Heinemann Educational 2001
Physics TB7 Topic help 7.3A
102
Physics TB7 Topic help 7.3B
charge conventional
current coulomb electron ion
charge conventional
current coulomb electron ion
M ? T
Using electricity1 The wire which carries current to domestic appliances.
2 The wire which provides a return path for current from a domesticappliance.
3 The wire which should carry no current unless a fault occurs.
4 A thin wire which breaks if the current gets too large.
5 Power is measured in units called
6 Current from the mains supply.
7 Current from a battery.
Using electricity
1 Finish the table by writing in the colours of each wire whenconnected to a normal 13A plug.
wire colour
live
neutral
earth
2 The current in an electric kettle is 8A. What fuse should be put inthe plug. Put a ring around the correct answer.
2A 5A 13A3 Jane connects a bulb and a d.c. ammeter to a 12V a.c. power pack.
Put a ring around the correct statement.
The bulb lights but theammeter vibrates around 0A.
The bulb does not light and theammeter reads 0A.
The bulb does not light and theammeter vibrates around 0A.
© Heinemann Educational 2001 103
Physics TB7 Topic help 7.4A
alternating current direct current earth fuse live neutral watt
Physics TB7 Topic help 7.4B
alternating current direct current earth fuse live neutral watt
A
M ? T
Using electricity1 Wiring of an electrical appliance in a way that no live wire can
possibly touch the casing.
2 Symptoms after an electric current has passed through the body.
3 The electricity supply companies measure electrical energy in unitscalled
4 The joining together of live and neutral wires without passingthrough the appliance.
5 Switch which turns off the current when it reaches a certain value.
6 Switch which turns off the current when a small difference betweenthe value of current in the live and neutral wires is detected.
Using electricity
1 What does this symbol on an electrical appliance mean?
2 A 2 kW fan heater is used for three hours.
(a) How much electrical energy has been used?____________ units.
(b) Electricity costs 7p per unit. How much does the heater cost to
use for three hours? _____________p
3 Finish these sentences
The live wire in a metal kettle is loose and touches the case. The
metal is connected to e_____________. A large c_____________
passes through the l_____________ wire. This melts the
f_____________.
4 Put a tick next to each correct statement about residual currentdevices.
An RCD does not detect a short circuit.
An RCD does not detect a large current in the live wire.
An RCD should be used as well as (not instead of) a fuse.
© Heinemann Educational 2001
Physics TB7 Topic help 7.5, 7.6A
104
Physics TB7 Topic help 7.5, 7.6B
circuit breaker double insulation electric shock kilowatt-hour residual current
device short circuit
circuit breaker double insulation electric shock kilowatt-hour residual current
device short circuit
M ? T
Electromagnetism1 A device which uses an electric current in a magnetic field to
produce motion.
2 Used to predict the direction of motion.
3 The field produced by the concave poles of a horseshoe magnet.
4 Former on which a coil is wound to increase the strength of themagnetic field.
5 Part of a motor which reverses the current direction in the coil.
6 Device which works on the motor principle which vibrates toproduce sound.
Electromagnetism
1 The diagram shows a wire passing between the poles of magnets.In which direction will the wire move when the switch is closed?Put a ring around the correct answer.
2 Which arrangement of magnetic poles will produce a radial field?Choose A, B or C.
3 Put a ring around the change which will decrease the speed of amotor.
increase number of turns on coil
increase current in wire
increase distance between magnetic poles
© Heinemann Educational 2001 105
Physics TB8 Topic help 8.1 and 8.2A
Fleming’sleft-hand rule
iron core loudspeaker motor radial field split-ring
commutator
Physics TB8 Topic help 8.1 and 8.2B
Fleming’sleft-hand rule
iron core loudspeaker motor radial field split-ring
commutator NS
N NS N S
CBA
N
M ? T
Electromagnetism1 Used to predict the direction of the current.
2 Relates the speed of cutting magnetic field lines to the voltageproduced.
3 Current produced when a wire moves through a magnetic field.
4 Voltage produced when a wire moves through a magnetic field.
Electromagnetism
1 The diagram shows a wiremoving downwards between thepoles of magnets. In whichdirection A or B willconventional current beproduced? ___________________
2 Michael winds a coil of wire around amagnet. He attaches the ends of thewire to an ammeter.
(a) What is the reading on theammeter? ___________________
(b) What three things can Michael doto increase the current?
Put rings around the correct answers.
increase the number of turns on the coil
decrease the number of turns on the coil
increase the strength of the magnet
decrease the strength of the magnet
move the magnet out of the coil
change the ammeter for a more sensitive one
© Heinemann Educational 2001
Physics TB8 Topic help 8.3A
106
Physics TB8 Topic help 8.3B
Faraday’s Law Fleming’s
right-hand rule induced current induced voltage
Faraday’s Law Fleming’s
right-hand rule induced current induced voltage
NS
B
A
A
N S
M ? T
Electromagnetism1 Device which uses mechanical energy to produce an electric
current.
2 An a.c. generator.
3 The production of a voltage in a coil of wire by the changingmagnetic field from an adjacent coil.
4 Device which conducts current via carbon brushes from the coil ofan a.c. generator.
Electromagnetism
1 The diagram shows two coils wound onto awooden rod. One coil is connected to aswitch and a battery. The other coil isconnected to an ammeter.
(a) What is the reading on the ammeterwhen the switch is open?
(b) What happens when the switch isclosed? Put a ring around the correctanswer.
The needle of the ammeter stays still.
The needle deflects then returns tozero.
The needle deflects and stays deflected.
(c) What happens when the switch is opened again? Put a ringaround the correct answer.
The needle of the ammeter stays still.
The needle deflects the opposite way then returns to zero.
The needle deflects the opposite way and stays deflected.
(d) What happens if the wooden rod is replaced with an iron rod?Finish the sentence.
The current induced in the bottom coil is ___________________ .
© Heinemann Educational 2001 107
Physics TB8 Topic help 8.4A
alternator dynamo mutual induction slip rings
Physics TB8 Topic help 8.4B
alternator dynamo mutual induction slip rings
A
M ? T
Electromagnetism
The input coil of a transformer.
The output coil of a transformer.
A transformer whose output voltage is greater than the input.
A transformer whose output voltage is less than the input.
Arrangement of thin layers of iron in the core of a transformer.
Induced in the core of a transformer.
Electromagnetism
1 The diagram shows a transformer.
(a) Finish labelling the diagram.
(b) What type of transformer, step-up or step-down, is shown?
(c) A 12 V d.c. supply is connected to the primary coil. Why isthere no output from the secondary coil? Put a ring around thecorrect answer.
The voltage is too low to make the transformer work.
Transformers only work if the voltage is a.c.
Iron is the wrong material on which to wind the coils.
© Heinemann Educational 2001
Physics TB8 Topic help 8.5A
108
Physics TB8 Topic help 8.5B
primary secondary step-down step-up eddy current laminated
primary secondary step-down step-up eddy current laminated
Primarycoil
Iron
M ? T
Electromagnetism1 The raising of the average temperature of the Earth.
2 Damage to the environment caused by man.
3 Oxides of sulphur dissolved in water.
4 d.c. generator providing current for electromagnets in a powerstation.
5 Water boiled at high pressure.
6 Source of energy which is not used up or which is replaced quickly.
7 Complex which produces electricity from another energy source.
Electromagnetism
1 Which three types of power station burn fossil fuels to produceelectricity? Choose your answers from the list.
_________________________ _________________________
_________________________
2 Which type of power station uses a renewable energy source?
Choose your answer from the list. ___________________
3 Which type of power station uses radioactive elements as a source?
Choose your answer from the list. ___________________
4 What damage does acid rain do to buildings?
5 What damage does acid rain do to plants and animals?
6 Put rings around other sources of energy which are beingdeveloped.
geothermal lightning solar
tide wind wave
© Heinemann Educational 2001 109
Physics TB8 Topic help 8.6A
acid rain exciter global warming pollution renewable energy superheated steam power station
Physics TB8 Topic help 8.6B
acid rain exciter global warming pollution renewable energy superheated steam
power stations coal-burning gas-fired hydroelectric nuclear oil-fired
M ? T
Electromagnetism1 The difference between the power generated and the power
available for use.
2 Distribution network carrying electricity from power station toconsumers.
3 The movement of electricity from one place to another.
4 A local transformer.
Electromagnetism
1 Electricity leaves the power station with a voltage of 25 000 V.
(a) The overhead power lines carry the electricity with a voltage of400 000 V. What type of transformer is used to change the voltage?
(b) Local substations change the voltage back to 230 V to use athome. What type of transformer is in the local substation?
2 Finish the sentences.
Electricity is transmitted around the country at high voltages. This
means that the c___________________ is small. Energy is lost from
the wires in the form of h___________________. The amount of
energy lost depends on the c___________________, so it is best if this
is as small as possible.
© Heinemann Educational 2001110
Physics TB8 Topic help 8.7A
Physics TB8 Topic help 8.7B
National Grid power loss substation transmission
National Grid power loss substation transmission
Powerstation
25 000 V
400 000 V
Home230 V
M ? T
TB1 Electric circuitsSpread 1.1
A Energy current resistance light dependentresistor thermistor variable resistor diode electron lightemitting diode.
B 1 (a) resistor, (b) diode,(c) variable resistor,(d) thermistor,(e) light emitting diode,
(f) light dependent resistor
2 arrow in anticlockwisedirection
Spread 1.2A Voltmeter ampere parallel volt ammeter.
B 1 (a) ammeter, (b) voltmeter
2 A in series V in parallel
3 (a) parallel, (b) series
Spread 1.3A Semiconductor ohmic milliamp
B 1 mA
2 1000
3 silicon
4 straight line passing throughorigin
TB2 Forces and energySpread 2.1
A Moment couple torque pivot newton metre equilibrium.
B 1 (a) left, (b) balanced,(c) balanced
2 leverage
Spread 2.2A Speed gradient tangent.
B 1 (a) D, (b) A, (c) A and B, (d) E,(e) E
2 60
3 (a) C, (b) A
Spread 2.3A Velocity vector scalar displacement.
B 1 25 m/s
2 mass, temperature
3 The car finished its journeyat the same place as itstarted. The car was notstationary at position D.
© Heinemann Educational 2001 111
Physics TB1 Topic help answers
A
A
A
A
A
A
A
M ?
Spread 2.4
A Decelaration and retardation acceleration gravity.
B 1 (a) D, (b) E, (c) A and B, (d) A,(e) E
2 (a) 10, (b) gravity
3 velocity, decelaration
Spread 2.5
A Force tension air resistance friction lift weight thrust drag
B 1 (a) lift, (b) friction, (c) gravity,(d) drag, (e) tension
2 F1 lift, F2 drag/air resistance,F3 weight, F4 thrust
Spread 2.6
A Resultant balanced unbalanced streamlined.
B 1 (a) true, (b) true, (c) false,(d) true
2 cone
Spread 2.8
A Joule Newton Watt work power gravitationalpotential kinetic.
B 1 Joule, Newton, Watt 2 (a) A, (b) D, (c) F, (d) E
Spread 2.9
A Reaction time thinking distance braking distance stoppingdistance.
B 1 (a) 15 m, (b) more than 7 m,(c) increase
2 age of driver, amount ofalcohol
3 road surface, state of brakes
Spread 2.10
A Gravity terminal velocity air resistance.
B 1 decrease
2 E
3 upwards
Spread 2.11+2.12
A Convection conduction radiation insulator machine pay back period.
B 1 (a) convection, (b) right
2 (a) conduction, (b) insulator
3 radiation
© Heinemann Educational 2001
Physics TB2 Topic help answers
112
A
A
A
A
A
A
A
M ?
TB3 Wave propertiesSpread 3.1
A Electromagnetic wave longitudinal wave transversewave vibration compression rarefaction.
B 1 sound, water
2 R where lines are far apart, Cwhere lines are close together
3 vertical arrow
4 horizontal arrow
Spread 3.2A Hertz wavelength amplitude frequency speed
velocity.
B 1 (a) amplitude, (b) wavelength
2 wavelength
3 0.5 Hz
Spread 3.3A Focus concave convex converge diverge wavefront
plane pulse ripple tank stroboscope.
B 1 (a) concave, (b) X at origin ofwaves, (c) diverge
2 circle
Spread 3.4+3.5A Normal incident ray reflected ray glancing angle diffuse
echo reverberation refraction.
B 1 (a) N on normal, (b) I on raytravelling towards mirror,(c) R on reflected ray, (d) G atangle between incident ray
and mirror
2 (a) N on normal, (b) raydeviated towards normal,(c) refraction
Spread 3.6+3.7A Image real image virtual image diffraction real depth
apparent depth no-parallax.
B 1 pinhole camera, overheadprojector
2 (a) at fish, (b) at end of virtualray above fish
3 behind the pointer
© Heinemann Educational 2001 113
Physics TB3 Topic help answers
A
A
A
A
A
M ?
TB4 Using waves
Spread 4.1
A Ultraviolet infrared X-rays spectrum fluorescent radio visible light.
B 1 red
2 pink, orange, purple
3 microwave
4 300 000 000m/s,300 000km/s
5 fluorescent
6 screen
Spread 4.2
A Thermistor thermograph.
B 1 glows red
2 infrared
3 ultraviolet
4 electric bar fire, night sights,remote control for hi-fi unit
5 four hours → factor 20, onehour → factor5, three hours→ factor 15, two hours →factor 10
Spread 4.3
A Aerial satellite gamma ray X-rays radio microwave radar ionosphere.
B 1 long – 2 km, medium –200 m, micro – 2 mm,short – 2 m
2 X-ray
Spread 4.4
A Endoscope optical fibre prism total internalreflection digital signal critical angle.
B 1 top two traces
2 (a) total internal reflection,(b) reflected through 90o at I,exit block normally,
(c) normal, angle ofincidence, prism
3 optical fibre
Spread 4.5
A Ultrasound sonar.
B 1 bat, dolphin, rat 2 sea bed, shoal of fish,submarine, sunken wreck
© Heinemann Educational 2001
Physics TB4 Topic help answers
114
A
A
A
A
A
M ?
Spread 4.7A Magma lava volcanic ash core crust mantle
lithosphere continental drift.
B 1 crust, mantle, core 2 volcanic ash, lava
Spread 4.8
A Asthenosphere metamorphism plate sea-floor spreading constructive boundary destructive boundary subductionzone trench.
B 1 sea-floor spreading 2 earthquakes
TB5 Radioactivity
Spread 5.1
A Alpha particle beta particle gamma ray isotope radioisotope antineutrino atomic number mass number background radiation.
B 1 (a) A=3 Z=6, (b) A=8 Z=14,(c) A=6 Z=14
2 (a) beta, (b) no change
3 (a) alpha, (b) decreases by 4
4 background radiation
Spread 5.2
A Spark counter film badge Geiger-Müller tube ionisation,radiation.
B 1 alpha
2 gamma
3 beta
4 gamma
5 do not ionise air enough
6 alpha
Spread 5.3
A Decay parent nuclide daughter nuclide half-life activity becquerel.
B 1 four hours
2 (a) radium-226, (b) radon-222
3 100 bq
© Heinemann Educational 2001 115
Physics TB5 Topic help answers
A
A
A
A
A
M ?
Spread 5.4+5.5
Bacteria cancer sterilise radiocarbon dating tracer.
B 1 gamma
2 beta
3 gamma
4 alpha
5 gamma
6 carbon-14
7 emits alpha radiation and hasa long half-life
Spread 5.6A Radiation sickness radiation burns DNA lymphocyte
mutation cumulative.
B 1 deoxyribonucleic acid
2 sixteen
3 shielding
4 radioactivity
TB6 The Earth and Universe
Spread 6.1A Centripetal gravity satellite planet asteroid comet
Solar System polar orbit geo-stationary orbit.
B 1 arrow from S towards centreof E
2 closer to Earth
Spread 6.2A Black hole nuclear fusion protostar white dwarf neutron
star red giant blue supergiant black dwarf nebulae supernova.
B 1 (a) hydrogen, (b) helium
2 gravity
3 white dwarf, red giant, redsupergiant
4 small star
Spread 6.3A Quasar Big Bang Big Crunch red shift Doppler effect.
B 1 nothing
2 G4
3 more than 12 billion years
4 blue, towards
5 towards
© Heinemann Educational 2001
Physics TB6 Topic help answers
116
A
A
A
A
A
M ?
TB7 Using electricity
Spread 7.1A Proton neutron electron nucleus charge conductor
insulator van de Graaff generator repel friction.
B 1 (a) negative, (b) positive
2 same number of protons aselectrons
3 negative
4 induction
Spread 7.2A Toner photocopier precipitator inert fuel lightning.
B 1 (a) negative, (b) positive
2 good conductor to prevent abuild up of charge
3 insulator, conductor,lightning
4 A
Spread 7.3A Coulomb electron ion charge conventional current.
B 1 (a) anticlockwise arrow,(b) clockwise arrow
2 negative
Spread 7.4A Live neutral earth fuse watt alternating current
direct current.
B 1 brown, blue, green andyellow
2 13A
3 bulb lights and ammetervibrates
Spread 7.5+7.6A Double insulation electric shock kilowatt-hour short
circuit circuit breaker residual current device.
B 1 double insulated
2 (a) 6, (b) 42p
3 earth, current, live fuse
4 Ticks next to all threestatements
TB8 Electromagnetism
Spread 8.1+8.2A Motor Fleming’s left-hand rule radial field iron core
split-ring commutator loudspeaker.
© Heinemann Educational 2001 117
Physics TB7 Topic help answers
A
A
A
A
A
A
M ?
B 1 downwards
2 C
3 increase distance betweenmagnetic poles
Spread 8.3A Fleming’s right-hand rule Faraday’s Law induced current
induced voltage.
B 1 B 2 (a) 0A, (b) increase turns,increase strength of magnet,move magnet
Spread 8.4A Dynamo alternator mutual induction slip rings.
B 1 (a) 0A,(b) needle deflects thenreturns to zero,
(c) needle deflects oppositeway then returns to zero,(d) increased
Spread 8.5A Primary secondary step-up step-down laminated
eddy current.
B 1 (a) secondary coil, iron core,(b) step-up, (c) transformers
only work if the voltage isa.c.
Spread 8.6A Global warming pollution acid rain exciter superheated
steam renewable energy power station.
B 1 coal-burning, gas-burning,oil-fired
2 hydroelectric
3 nuclear
4 dissolves rock
5 kills trees and fish, forexample
6 geothermal, solar, tide, wind,wave
Spread 8.7A Power loss National Grid transmission substation.
B 1 (a) step-up, (b) step-down 2 current, heat, current
© Heinemann Educational 2001
Physics TB8 Topic help answers
118
A
A
A
A
A
M ?
Electric circuits1 Solve the clues and fill in the squares with the electrical words.
1 Energy source. 2 Connection of electrical components.3 Same current in these resistors. 4 Usually different current in these resistors.5 Work done in taking current through component.6 Electrical quantity with greek symbol. 7 Used to measure current.
2 Rearrange the letters in this anagram to make voltageproportional to current.
SLOW HAM3 Finish this sentence.
A device whose resistance changes with temperature is called a _ _ _ _ _ _ _ _ _
4 True or false?
The resistance of a wire increases as its length increases.
The current in a wire increases as its length increases.
Thick iron wire has a higher resistance than the same length ofthin iron wire.
5 Match the components to their voltage current graphs.
© Heinemann Educational 2001 119
Physics TB1 Self-assessment TB1 Foundation
C1
U2
3
4
5
6
7
RRENT
V
I
V
I
V
I
Bulb
Diode
Resistor
M ? T
Electric circuits1 Solve the clues and fill in the squares with the electrical words.
1 Energy source. 2 Connection of electrical components.3 Same current in these resistors. 4 Usually different current in these resistors.5 Work done in taking current through component.6 Electrical quantity with greek symbol. 7 Used to measure current.
2 Rearrange the letters in this anagram to make voltageproportional to current.
SLOW HAM OHM’S LAW3 Finish this sentence.
A device whose resistance changes with temperature is called a thermistor.
4 True or false?
The resistance of a wire increases as its length increases. T
The current in a wire increases as its length increases. F
Thick iron wire has a higher resistance than the same length ofthin iron wire. F
5 Match the components to their voltage current graphs.
© Heinemann Educational 2001
Physics TB1 Self-assessment answers TB1 Foundation
120
C1
U2
3
4
5
6
7
RRENT
EC I R
SPATM
TSM
LIA
OS
VER
EAGAE
IA
CE
EL
ER
SL E L
C I TL L
V
I
V
I
V
I
Bulb
Diode
Resistor
AM ?
Electric circuits1 Solve the clues and fill in the squares with electrical words.
1 Current particle. 2 Temperature dependent device.3 Circuit flower. 4 Illuminating device.5 Rotator. 6 Impedes current.7 Measures voltage. 8 One way device.
2 Rearrange the letters in this anagram to make poor electricalcurrent passage.
NOT RUDE COMICS
3 Finish this sentence.
A device which emits light when a current passes through it in
one particular direction is called a
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
4 True or false?
The resistance of an LDR increases as the lightintensity increases.
The resistance of a thermistor increases as thetemperature increases.
The resistance of a wire increases as its temperatureincreases.
5 Arrange the ammeter readings in this circuit in order startingwith the lowest.
© Heinemann Educational 2001 121
Physics TB1 Self-assessment TB1 Higher
1
2
3
8
4
5
7
6
A3
A2
20 Ω
10 Ω
A5
A4
200 Ω
1 Ω
A1
TTM ?
Electric circuits1 Solve the clues and fill in the squares with electrical words.
1 Current particle. 2 Temperature dependent device.3 Circuit flower. 4 Illuminating device.5 Rotator. 6 Impedes current.7 Measures voltage. 8 One way device.
2 Rearrange the letters in this anagram to make poor electricalcurrent passage.
NOT RUDE COMICS SEMICONDUCTOR3 Finish this sentence.
A device which emits light when a current passes through it in
one particular direction is called a light emitting diode.
4 True or false?
The resistance of an LDR increases as the lightintensity increases. F
The resistance of a thermistor increases as thetemperature increases. F
The resistance of a wire increases as its temperatureincreases. T
5 Arrange the ammeter readings in this circuit in order startingwith the lowest.
© Heinemann Educational 2001
Physics TB1 Self-assessment answers TB1 Higher
122
ORTCEL NT H E R M I S T O R
V O L T M E ET R
G ERAHCL A M P
T O RRS T O
M OR SE I
E1
2
3
EDOID8
4
5
7
6
A3
A2
20 Ω
10 Ω
A5
A4
200 Ω
1 Ω
A1 35
4
2 1
AM ?
Forces and energy1 Solve the clues and fill in the squares with the types of forces.
Find the name of a scientist
1 A turning force at a distance. 2 Equal and opposite to an action.3 Vertical force acting on a mass. 4 Force which causes 3.5 Force between surfaces. 6 Force in a stretched spring.
2 Rearrange the letters in this anagram to make something whichis stored.
TEEN GIRL EAT PONY
3 Draw a straight line from each quantity to its correct unit.Write in the symbols for each unit. One has been done for you.
4 Finish these sentences.
A poor conductor is known as an _ _ _ _ _ _ _ _ _.
Energy from the Sun reaches us by the process of _ _ _ _ _ _ _ _ _.
Energy is transferred through fluids by the process of _ _ _ _ _ _ _ _ _ _.
5 True or false?
The gradient of a velocity time graph gives the speed ofa body.
The distance travelled by a body is the area under avelocity time graph.
A straight line distance time graph means the body isaccelerating.
Displacement is a vector and distance is a scalar.
A body needs a force acting on it before it willaccelerate.
© Heinemann Educational 2001 123
Physics TB2 Self-assessment TB2 Foundation
1
2
5
6
4
3
Acceleration
Energy
Power
Thrust
Torque
Velocity
Joule
Metre per second
Metre per second squared
Newton
Newton metre
Watt
N
TM ?
Forces and energy1 Solve the clues and fill in the squares with the types of forces.
Find the name of the scientist. NEWTON1 A turning force at a distance. 2 Equal and opposite to an action.3 Vertical force acting on a mass. 4 Force which causes 3.5 Force between surfaces. 6 Force in a stretched spring.
2 Rearrange the letters in this anagram to make something whichis stored.
TEEN GIRL EAT PONY POTENTIAL ENERGY3 Draw a straight line from each quantity to its correct unit.
Write in the symbols for each unit. One has been done for you.
4 Finish these sentences.
A poor conductor is known as an insulator.
Energy from the Sun reaches us by the process of radiation.
Energy is transferred through fluids by the process of convection.
5 True or false?
The gradient of a velocity time graph gives the speed ofa body. F
The distance travelled by a body is the area under avelocity time graph. T
A straight line distance time graph means the body isaccelerating. F
Displacement is a vector and distance is a scalar. T
A body needs a force acting on it before it willaccelerate. T
© Heinemann Educational 2001
Physics TB2 Self-assessment answers TB2 Foundation
124
1
2
5
6
TNEMOM
VA4G R
TT
CIRFIIE
EWTON
YNS
I
I O N
G H TR AE C T I O N
3
Acceleration
Energy
Power
Thrust
Torque
Velocity
Joule
Metre per second
Metre per second squared
Newton
Newton metre
Watt
N
Jm/s
m/s2
Nm
W
AM ?
Forces and energy1 Solve the clues and fill in the squares with the mechanical words.
Which three are not vectors?
1 Rate of motion in astraight line.
2 Rate of motion.3 How far a body has
moved.4 The action of moving
faster.5 Causes 4.6 Needed for work to be
done.7 The amount of material
in a body.
2 Rearrange the letters in this anagram to make a weight-to-mass ratio.
VISIT EARTH AND FORGETTING ALL
3 Finish these sentences.
The part of a car which collapses on impact is called
the _ _ _ _ _ _ _ _ _ _ _.
This helps to reduce the _ _ _ _ _ _ _ _ _ _ _ _ on the occupants
by increasing the time to stop.
4 True or false?
A falling body loses gravitational potential energy andgains kinetic energy.
The total energy of a falling body remains constant.
The temperature of water at the bottom of a waterfallis lower than at the top.
Some machines can be 100% efficient.
A small amount of energy from the Sun reaches Earthby convection.
5 Arrange the following in order of force needed to move theobject, starting with the smallest.
A 5 kg mass of lead falling at a constant velocity through thicktreacle.A 2 kg bag of sugar with an acceleration of 1.5 m/s2 across asmooth surface.A 500 g jar of jam with an acceleration of 8 m/s2 with anopposing frictional force of 2 N.A 100 g apple with an acceleration of 10 m/s2 falling freelyunder gravity.
© Heinemann Educational 2001 125
Physics TB2 Self-assessment TB2 Higher
VE
S
CTOR
1
2
3
4
5
7
6
TTM ?
Forces and energy1 Solve the clues and fill in the squares with the mechanical words.
Which three are not vectors? SPEED ENERGY MASS1 Rate of motion in a
straight line.2 Rate of motion.3 How far a body has
moved.4 The action of moving
faster.5 Causes 4.6 Needed for work to be
done.7 The amount of material
in a body.
2 Rearrange the letters in this anagram to make a weight-to-mass ratio.
VISIT EARTH AND FORGETTING ALL GRAVITATIONAL FIELD STRENGTH3 Finish these sentences.
The part of a car which collapses on impact is called
the crumple zone.
This helps to reduce the deceleration on the occupants by
increasing the time to stop.
4 True or false?
A falling body loses gravitational potential energy andgains kinetic energy. T
The total energy of a falling body remains constant. T
The temperature of water at the bottom of a waterfallis lower than the top. F
Some machines can be 100% efficient. F
A small amount of energy from the Sun reaches Earthby convection. F
5 Arrange the following in order of force needed to move theobject, starting with the smallest.
A 5 kg mass of lead falling at a constant velocity through thicktreacle. – 1A 2 kg bag of sugar with an acceleration of 1.5 m/s2 across asmooth surface. – 3A 500 g jar of jam with an acceleration of 8 m/s2 with anopposing frictional force of 2 N. – 4A 100 g apple with an acceleration of 10 m/s2 falling freelyunder gravity. – 2
© Heinemann Educational 2001
Physics TB2 Self-assessment answers TB2 Higher
126
VS EP E D
E L O C I
M EN
N T
T Y
S
C EALID PSAREC ELA T I O
O R CG Y
F EE EN R
1
2
3
SAM
4 C5
7
6
AM ?
Wave properties1 Solve the clues and fill in the squares with the properties of
images.
1 Cannot be projected onto a screen. 2 Larger.3 Can be projected onto a screen. 4 The same way up.5 Upside down. 6 Smaller.
2 Rearrange the letters in this anagram to make two types ofwaves.
VALS TRAIN RENT IS LONG DUE
3 Match each word with its description.
amplitude distance between two peaks of a wave
frequency maximum displacement from rest
speed number of waves passing a point in one second
wavelength how fast the wave is moving
4 Finish this sentence.
When a wave spreads out after passing through a gap this is
known as _ _ _ _ _ _ _ _ _ _ _.
5 True or false?
The angle of incidence always equals the angle ofreflection.
The angle of incidence is always less than or equal tothe angle of refraction.
A normal ray is one at 180° to the surface.
A ray of light entering a glass block along the normal isnot refracted.
Multiple reflections of sound are call reverberations.
6 Arrange the following in order of speed, starting with theslowest.
light wave
sound wave
water wave
© Heinemann Educational 2001 127
Physics TB3 Self-assessment TB3 Foundation
I1
M2
4
5
6
AGES
3
TTM ?
Wave properties1 Solve the clues and fill in the squares with the properties of
images.
1 Cannot be projected onto a screen. 2 Larger.3 Can be projected onto a screen. 4 The same way up.5 Upside down. 6 Smaller.
2 Rearrange the letters in this anagram to make two types ofwaves.
VALS TRAIN RENT IS LONG DUE TRANSVERSE LONGITUDINAL
3 Match each word with its description.
amplitude distance between two peaks of a wave
frequency maximum displacement from rest
speed number of waves passing a point in one second
wavelength how fast the wave is moving
4 Finish this sentence.
When a wave spreads out after passing through a gap this is
known as diffraction.
5 True or false?
The angle of incidence always equals the angle ofreflection. T
The angle of incidence is always less than or equal tothe angle of refraction. F
A normal ray is one at 180° to the surface. F
A ray of light entering a glass block along the normal isnot refracted. T
Multiple reflections of sound are call reverberations. T6 Arrange the following in order of speed, starting with the
slowest.light wave – 3sound wave – 2water wave – 1
© Heinemann Educational 2001
Physics TB3 Self-assessment answers TB3 Foundation
128
I1
M2
4
5
6
AGES
R
RNN
IIMID
E3RIU PVI
H
H
LT
R T E DDE
VA G N EFI I D
T U A L
AM ?
Wave properties1 All of the answers end in ION.
Which ION is another word meaning oscillation?
Which ION bounces back from a surface?
Which ION spreads out through a gap?
Which ION changes direction at a boundary?
Which ION is squeezed longitudinally?
Which ION is a continuous echo?
Which ION is stretched out longitudinally?
2 Rearrange the letters in this anagram to make two depths.
LEAP NEAR TRAP
3 Draw a straight line from each quantity to its correct unit.Write in the symbols for each unit.
4 Finish this sentence.
Waves transfer _ _ _ _ _ _ from one place to another without
transferring _ _ _ _ _ _.
5 True or false?
Plane waves incident at a concave barrier diverge afterreflection.
Plane waves incident at a straight barrier obey the lawsof reflection.
Curved waves incident at a straight barrier arereflected as straight waves.
When waves enter a shallower region of water thewave speed decreases.
Water waves spread out if the size of gap andwavelength are the same.
6 Arrange the following in order of speed, starting with the slowest.
a sound wave in air of frequency 110 Hz and wavelength 3.0 m
a sound wave in aluminium of frequency 500 Hz andwavelength 12.8 m
a sound wave in concrete of frequency 250 Hz and wavelength20.0 m
a sound wave in steel of frequency 50 Hz and wavelength120.0 m
a sound wave in water of frequency 1 kHz and wavelength 1.5 m
© Heinemann Educational 2001 129
Physics TB3 Self-assessment TB3 Higher
I O NI O NI O NI O NI O NI O NI O N
wavelength
velocity
frequency
metre per second
metre
hertz
M ? T
Wave properties1 All of the answers end in ION.
Which ION is another word meaning oscillation?
Which ION bounces back from a surface?
Which ION spreads out througha gap?
Which ION changes direction at a boundary?
Which ION is squeezed longitudinally?
Which ION is a continuous echo?
Which ION is stretched out longitudinally?
2 Rearrange the letters in this anagram to make two depths.
LEAP NEAR TRAP REAL APPARENT3 Draw a straight line from each quantity to its correct unit.
Write in the symbols for each unit.
4 Finish this sentence.
Waves transfer energy from one place to another without
transferring matter.
5 True or false?
Plane waves incident at a concave barrier diverge afterreflection. F
Plane waves incident at a straight barrier obey the lawsof reflection. T
Curved waves incident at a straight barrier arereflected as straight waves. F
When waves enter a shallower region of water thewave speed decreases. T
Water waves spread out if the size of gap andwavelength are the same. T
6 Arrange the following in order of speed, starting with the slowest.
a sound wave in air of frequency 110 Hz and wavelength 3.0 m – 1a sound wave in aluminium of frequency 500 Hz and wavelength12.8 m – 5a sound wave in concrete of frequency 250 Hz and wavelength20.0 m – 3a sound wave in steel of frequency 50 Hz and wavelength 120.0 m – 4a sound wave in water of frequency 1 kHz and wavelength 1.5 m – 2
© Heinemann Educational 2001
Physics TB3 Self-assessment answers TB3 Higher
130
R TAV BI I O NE TCER LF I O NA TCFID
OC
AREVER
RF I O NA TCER RF I O NE SSM RP I O NR TAR EB I O NA TCR FE I O N
wavelength
velocity
frequency
metre per second
metre
hertz
m/smHz
AM ?
Using waves1 Solve the clues and fill in the squares with the types of waves.
What word reads vertically?
1 They detect broken bones. 2 Used by Newton to make a rainbow.3 Used in remote control devices. 4 Cook or send messages with this wave.5 Causes a nice tan. 6 Longest electromagnetic wave.7 Beyond human hearing. 8 Very penetrating.
2 Rearrange the letters in this anagram to make a lighttransmitter.
CABLE IS PROFIT
3 Which two parts of the Earth form the lithosphere?Put rings around the correct answers.
crust inner core outer core outer mantle
4 Finish this sentence.
The angle at which light leaving a more dense material is reflected
instead of refracted is known as the _ _ _ _ _ _ _ _ angle.
5 True or false?
All electromagnetic waves are transverse waves.
No light is emitted from fluorescent materials.
An endoscope works because of total internalrefraction.
Lava comes from the molten core of the Earth.
Red flames are hotter than blue flames.
6 Arrange the following in order of wavelength, starting with theshortest.
blue gamma microwave
red ultraviolet yellow
© Heinemann Educational 2001 131
Physics TB4 Self-assessment TB4 Foundation
1
2
3
4
5
7
8
6
TTM ?
Using waves1 Solve the clues and fill in the squares with the types of waves.
What word reads vertically? SPECTRUM1 They detect broken bones. 2 Used by Newton to make a rainbow.3 Used in remote control devices. 4 Cook or send messages with this wave.5 Causes a nice tan. 6 Longest electromagnetic wave.7 Beyond human hearing. 8 Very penetrating.
2 Rearrange the letters in this anagram to make a lighttransmitter.
CABLE IS PROFIT OPTICAL FIBRES3 Which two parts of the Earth form the lithosphere?
Put rings around the correct answers.
crust inner core outer core outer mantle
4 Finish this sentence.
The angle at which light leaving a more dense material is reflected
instead of refracted is known as the critical angle.
5 True or false?
All electromagnetic waves are transverse waves. T
No light is emitted from fluorescent materials. F
An endoscope works because of total internalrefraction. F
Lava comes from the molten core of the Earth. F
Red flames are hotter than blue flames. F
6 Arrange the following in order of wavelength, starting with theshortest.
blue – 3 gamma – 1 microwave – 6red – 5 ultraviolet – 2 yellow – 4
© Heinemann Educational 2001
Physics TB4 Self-assessment answers TB4 Foundation
132
S1
P2
3
4
5
7
ECTRU
X R A
AMU
TLU
RIL
R A S O
DR
AN
FO
D I OD
8 MG A M A
RI NW A V E
R A V I O L E T
YR I S M
6
AM ?
Using waves1 Solve the clues and fill in the squares with seismic and Earth structure words.
Why is the vertical word not a good place to be?
1 Transverse earthquake wave. 2 This travels through the centre of the Earth.3 Detect earth vibrations. 4 The origin of an earthquake.5 The outer parts of the Earth. 6 The major part of the Earth.7 Fracture of rock. 8 Thin surface layer.9 The Earth’s central region.
2 Rearrange the letters in this anagram to make land movement.
CANNOT FIND LITTER
3 Which two travel at the same speed? Put rings around thecorrect answers.
p waves radio waves s waves visible light4 Finish these sentences.
An area where the oceanic plate descends beneath the
continental plate is known as a _ _ _ _ _ _ _ _ _ _ _ _ _ _.
The increased temperature and pressure can cause
_ _ _ _ _ _ _ _ _ _ _ _ producing new rocks by recrystallisation.
5 True or false?
The boundaries between colliding plates aredestructive plate boundaries.
Lithosphere is destroyed at constructive anddestructive plate boundaries.
The rate of sea-floor spreading is about two to threemillimetres per year.
New crust is formed from magma when two plates aremoving apart.
A trench forms when the continental plate moves upover the oceanic plate.
© Heinemann Educational 2001 133
Physics TB4 Self-assessment TB4 Higher
1
2
3
8
4
5
7
9
6
TTM ?
Using waves1 Solve the clues and fill in the squares with seismic and Earth
structure words. Why is the vertical word not a good place to
be? EPICENTRE – The place on the Earth’s surfaceimmediately above the origin of an earthquake.
1 Transverse earthquake wave. 2 This travels through the centre of the Earth.3 Detect earth vibrations. 4 The origin of an earthquake.5 The outer parts of the Earth. 6 The major part of the Earth.7 Fracture of rock. 8 Thin surface layer.9 The Earth’s central region.
2 Rearrange the letters in this anagram to make land movement.
CANNOT FIND LITTER CONTINENTAL DRIFT3 Which two travel at the same speed? Put rings around the
correct answers.
p waves radio waves s waves visible light4 Finish these sentences.
An area where the oceanic plate descends beneath the
continental plate is known as a subduction zone.
The increased temperature and pressure can cause
metamorphism producing new rocks by recrystallisation.
5 True or false?
The boundaries between colliding plates aredestructive plate boundaries. T
Lithosphere is destroyed at constructive anddestructive plate boundaries. F
The rate of sea-floor spreading is about two to threemillimetres per year. F
New crust is formed from magma when two plates aremoving apart. T
A trench forms when the continental plate moves upover the oceanic plate. T
© Heinemann Educational 2001
Physics TB4 Self-assessment answers TB4 Higher
134
VAWS EP W A V E
M O M
TF A U L
I S T E REESO C U S
E R ET L E
P HAM N
1
2
3
RE
TSUC8
F4
L I T H O S5
7
C O R9
6
AM ?
Radioactivity1 Solve the clues and fill in the squares with the names of seven
particles. Which particle reads vertically?
1 A type of atom. 2 The centre of an atom.3 A positive particle. 4 A negative particle.5 A neutral particle. 6 Helium nucleus.7 Radioactive electron.
2 Rearrange the letters in this anagram to make the surnames oftwo nuclear scientists.
EEC CLUB REQUIRE3 Which two things detect radioactivity? Put rings around the
correct answers.
film badge seismometer spark counter thermometer
4 Finish this sentence.
When a radioisotope emits radiation and changes into another
isotope this is known as radioactive _ _ _ _ _.
5 Arrange the following in order of mass, starting with the lightest.
alpha particle beta particlehydrogen atom proton
6 True or false?
The mass number is the total number of protons andneutrons
The atomic number is the number of neutrons
Isotopes of an element have the same atomic number
When an isotope emits an alpha particle, its massincreases by four
7 Which type of radiation is used for each job?smoke detector
thickness measurement of aluminium sheet
sterilising food
© Heinemann Educational 2001 135
Physics TB5 Self-assessment TB5 Foundation
3
5
6
7
2
4
1
TTM ?
Radioactivity1 Solve the clues and fill in the squares with the names of seven
particles. Which particle reads vertically? ISOTOPE1 A type of atom. 2 The centre of an atom.3 A positive particle. 4 A negative particle.5 A neutral particle. 6 Helium nucleus.7 Radioactive electron.
2 Rearrange the letters in this anagram to make the surnames oftwo nuclear scientists.
EEC CLUB REQUIRE CURIE BECQUEREL3 Which two things detect radioactivity? Put rings around the
correct answers.
film badge seismometer spark counter thermometer
4 Finish this sentence.
When a radioisotope emits radiation and changes into another
isotope this is known as radioactive decay.
5 Arrange the following in order of mass, starting with the lightest.
alpha particle – 4 beta particle – 1hydrogen atom – 3 proton – 2
6 True or false?
The mass number is the total number of protons andneutrons T
The atomic number is the number of neutrons F
Isotopes of an element have the same atomic number T
When an isotope emits an alpha particle, its massincreases by four F
7 Which type of radiation is used for each job?smoke detector α
thickness measurement of aluminium sheet γ
sterilising food γ
© Heinemann Educational 2001
Physics TB5 Self-assessment answers TB5 Foundation
136
3
5
6
7
DC L2N U E
PETA
UEN
RC
4E L
RLB
TRNHT
OO
AA
NN
U
1N U C L
OTOPE
SI E
AM ?
Radioactivity1 Fill in the squares with safety precautions.
2 Rearrange the letters in this anagram to find something whichis always around us.
DIG OUT ROCK AND A BRAIN
3 Which two particles have the same mass? Put rings around thecorrect answers.
alpha particle beta particle helium nucleus proton
4 Finish these sentences.
When radiation passes through a material, the atoms of the
material have electrons removed causing them to be
_ _ _ _ _ _ _ _ _ _ charged.
This process is known as _ _ _ _ _ _ _ _ _ _.
5 Draw a straight line from each radioactive decay to its product.
6 The uses are correct, but are the reasons true or false?
95241 Am is used in smoke detectors because it has ashort half life.
2760 Co is used for cancer treatment because it is verypenetrating.
1214 C is used to date artefacts because it is not verypenetrating.
95241 Am is used in a canning plant because it is verypenetrating.
7 A radioactive material has a mass of 150 g. What is the totalmass of material after three half lives have passed? Put a ringaround the correct answer.
150 g 75 g 37.5 g 18.75 g
© Heinemann Educational 2001 137
Physics TB5 Self-assessment TB5 Higher
Ra decays by the emission of an alpha particle to form226
88
Am decays by the emission of an alpha particle to form241
95
Cf decays by the emission of an alpha particle to form241
98
Po decays by the emission of a beta particle to form218
84
Na decays by the emission of a beta particle to form24
11
C decays by the emission of a beta particle to form14
6
At218
85
Cm237
93
Mg24
12
N14
7
Np237
96
Rn222
86
DECAY
1
2
3
4
5
TTM ?
Radioactivity1 Fill in the squares with safety precautions.
2 Rearrange the letters in this anagram to find something whichis always around us.
DIG OUT ROCK AND A BRAIN BACKGROUND RADIATION3 Which two particles have the same mass? Put rings around the
correct answers.
alpha particle beta particle helium nucleus proton
4 Finish these sentences.
When radiation passes through a material, the atoms of the
material have electrons removed causing them to be
positively charged.
This process is known as ionisation.
5 Draw a straight line from each radioactive decay to its product.
6 The uses are correct, but are the reasons true or false?
95241 Am is used in smoke detectors because it has ashort half life. F
2760 Co is used for cancer treatment because it is verypenetrating. T
1214 C is used to date artefacts because it is not verypenetrating. F
95241 Am is used in a canning plant because it is verypenetrating. T
7 A radioactive material has a mass of 150 g. What is the totalmass of material after three half lives have passed? Put a ringaround the correct answer.
150 g 75 g 37.5 g 18.75 g
© Heinemann Educational 2001
Physics TB5 Self-assessment answers TB5 Higher
138
DT MI E
S H I E L
I OE
N
I N G
C TERD ITSID A N C
YI VC T TI
1
2
3
4
A5
Ra decays by the emission of an alpha particle to form226
88
Am decays by the emission of an alpha particle to form241
95
Cf decays by the emission of an alpha particle to form241
98
Po decays by the emission of a beta particle to form218
84
Na decays by the emission of a beta particle to form24
11
C decays by the emission of a beta particle to form14
6
At218
85
Cm237
93
Mg24
12
N14
7
Np237
96
Rn222
86
AM ?
The Earth and Universe1 Finish filling in the squares with the names of six planets.
Which planet reads vertically?
2 Rearrange the letters in this anagram to make two planets.
TEEN HUNT PEAR
3 Which two things orbit Earth? Put rings around the correctanswers.
asteroid comet moon satellite
4 Finish this sentence.
The name of the force which keeps the planets in orbit around
the Sun is _ _ _ _ _ _ _.
5 Arrange the following in order of size, starting with thesmallest.
comet galaxy
planet solar system
star universe
6 True or false?
An object in geo-stationary orbit takes 12 hours toorbit the Earth.
An object in geo-stationary orbit never passes over thepoles.
A centrifugal force keeps things moving in a circle.
Objects closer to Earth travel faster in their orbit.
7 Put the phases of the life cycle of a star in the right order.
adult star blue supergiant
nebulae protostar
red supergiant supernova
8 We know that the Universe is expanding because
of _ _ _ _ _ _ _ _. Choose from
red eye red giant red light red shift
© Heinemann Educational 2001 139
Physics TB6 Self-assessment TB6 Foundation
1
2
3
4
5L
US
J
6
TTM ?
The Earth and Universe1 Finish filling in the squares with the names of six planets.
Which planet reads vertically? URANUS
2 Rearrange the letters in this anagram to make two planets.
TEEN HUNT PEAR EARTH NEPTUNE3 Which two things orbit Earth? Put rings around the correct
answers.
asteroid comet moon satellite
4 Finish this sentence.
The name of the force which keeps the planets in orbit around
the Sun is gravity.
5 Arrange the following in order of size, starting with thesmallest.
comet – 1 galaxy – 5planet – 2 solar system – 4star – 3 universe – 6
6 True or false?
An object in geo-stationary orbit takes 12 hours toorbit the Earth. F
An object in geo-stationary orbit never passes over thepoles. T
A centrifugal force keeps things moving in a circle. F
Objects closer to Earth travel faster in their orbit. T7 Put the phases of the life cycle of a star in the right order.
adult star – 3 blue supergiant – 4
nebulae – 1 protostar – 2
red supergiant – 5 supernova – 6
8 We know that the Universe is expanding because of red shift.Choose from
red eye red giant red light red shift
© Heinemann Educational 2001
Physics TB6 Self-assessment answers TB6 Foundation
140
1
2
3
4
5
PM
P
M
L
RU
A
SS
T OT U R N
EJ
CU
ANEV
SU
R U R YI T E R
6
AM ?
The Earth and Universe1 Solve the clues and fill in the squares with universal bodies and effects.
1 A cloud of gas and dust. 2 Effect causing frequency shift.3 A most distant visible object. 4 A cloud of dust and ice.5 A cold, dead star. 6 Astronomer who gave his name to a telescope.7 Rock between Mars and Jupiter. 8 One of nine in solar orbit.9 Sputnik was the first man-made one.
2 Rearrange the letters in this anagram to make two galaxies.
MANDY WAKE DIM ROYAL
3 Which space body is the odd one out and why? Put a ringaround the correct answer.
neutron red giant supernova white dwarf
4 Finish this sentence.
The Universe is believed to have begun with a large explosion
known as the _ _ _ _ _ _ _.
5 Arrange the following in order of speed, starting with theslowest.
GOES weather satellite in orbit 36 000 km above the EarthHubble Space telescope in orbit 600 km above the EarthInternational Space Station in orbit 390 km above the EarthNOAA weather satellite in orbit 830 km above the Earth
6 True or false?
A galaxy moving away from us appears redder thanusual.
The faster a galaxy is moving, the smaller the amountof red shift.
The age of the Universe is estimated to be at leasttwelve billion years.
The end of the Universe will be the big crunch.
© Heinemann Educational 2001 141
Physics TB6 Self-assessment TB6 Higher
BLACK
1
2
3
4
5
H6
O7
L8
E9
TTM ?
The Earth and Universe1 Solve the clues and fill in the squares with universal bodies and effects.
1 A cloud of gas and dust. 2 Effect causing frequency shift.3 A most distant visible object. 4 A cloud of dust and ice.5 A cold, dead star. 6 Astronomer who gave his name to a telescope.7 Rock between Mars and Jupiter. 8 One of nine in solar orbit.9 Sputnik was the first man-made one.
2 Rearrange the letters in this anagram to make two galaxies.
MANDY WAKE DIM ROYAL MILKY WAY ANDROMEDA3 Which space body is the odd one out and why? Put a ring
around the correct answer.
neutron red giant supernova white dwarf It is not a type of star.4 Finish this sentence.
The Universe is believed to have begun with a large explosion
known as the big bang.
5 Arrange the following in order of speed, starting with theslowest.
GOES weather satellite in orbit 36 000 km above the Earth – 1Hubble Space telescope in orbit 600 km above the Earth – 3International Space Station in orbit 390 km above the Earth – 4NOAA weather satellite in orbit 830 km above the Earth – 2
6 True or false?
A galaxy moving away from us appears redder thanusual. T
The faster a galaxy is moving, the smaller the amountof red shift. F
The age of the Universe is estimated to be at leasttwelve billion years. T
The end of the Universe will be the big crunch. F
© Heinemann Educational 2001
Physics TB6 Self-assessment answers TB6 Higher
142
BO PP L
N E
A RE
U LE R
A
A SUQTC O M
A R FD WKB L CA
1
D2
3
4
5
B L EU BH6
I DOA TS RE7
E TA NLP8
I T EL LES TA9
AM ?
Using electricity1 Solve the clues and fill in the squares with the electrical
quantities or properties. What wire reads vertically?
1 A charged particle. 2 Protect from high 4.3 Unit of charge. 4 A flow of charge.5 Rate of using energy. 6 The safety wire.7 The brown wire.
2 Rearrange the letters in this anagram to make electrical energy.
WAIT RUTH – LOOK
3 Which two devices work because of electrostatics?
Put rings around the correct answers.
ink jet printer light bulb photocopier transformer
4 Finish this sentence.
If an object loses electrons, it becomes _ _ _ _ _ _ _ _ _ _
charged.
5 True or false?
Like charges attract
Power = voltage ÷ current.
The electrical supply from the mains is alternatingcurrent.
An RCD detects a small current change between theearth and neutral wires.
A double insulated device does not have an earth wire.
6 Arrange the following in order of energy usage, starting withthe lowest.
60 W bulb used for 4 hours100 W computer for 1 hour1 kW iron for 10 minutes2.5 kW kettle for 3 minutes3 kW fire for 1 hour
© Heinemann Educational 2001 143
Physics TB7 Self-assessment TB7 Foundation
1
2
3
4
5
6
7
TTM ?
Using electricity1 Solve the clues and fill in the squares with the electrical
quantities or properties. What wire reads vertically? NEUTRAL1 A charged particle. 2 Protect from high 4.3 Unit of charge. 4 A flow of charge.5 Rate of using energy. 6 The safety wire.7 The brown wire.
2 Rearrange the letters in this anagram to make electrical energy.
WAIT RUTH – LOOK KILOWATT – HOUR3 Which two devices work because of electrostatics?
Put rings around the correct answers.
ink jet printer light bulb photocopier transformer
4 Finish this sentence.
If an object loses electrons, it becomes positivelycharged.
5 True or false?
Like charges attract F
Power = voltage ÷ current. F
The electrical supply from the mains is alternatingcurrent. T
An RCD detects a small current change between theearth and neutral wires. F
A double insulated device does not have an earth wire. T6 Arrange the following in order of energy usage, starting with
the lowest.
60 W bulb used for 4 hours – 4100 W computer for 1 hour – 11 kW iron for 10 minutes – 32.5 kW kettle for 3 minutes – 23 kW fire for 1 hour – 5
© Heinemann Educational 2001
Physics TB7 Self-assessment answers TB7 Foundation
144
N1
E2
3
4
5
6
UTRAL
IF U
CEWOP
ONEE
L
RI
OC
TV
HE
BMU R R
SO
7
AM ?
Using electricity1 All of the answers end in ION.
Which ION causes charging by rubbing?
Which ION makes unlike charges move together?
Which ION makes like charges move apart?
Which ION allows electrons to move through a metal?
Which ION causes opposite charges by contact?
2 Rearrange the letters in this anagram to make shocking piece ofequipment.
RAT OF FEARED VEGAN GRAN
3 Which two wires are connected to the ground either at thehouse or at the power station? Put rings around the correctanswers.
earth fuse live neutral
4 Draw a straight line between the boxes to complete theequations. Write the correct unit in the box next to thequantity.
5 True or false?
It is important to connect an aircraft to its tankerbefore refuelling.
Oil tankers are filled with hydrogen gas before cleaningto avoid explosions.
Air can become a conductor between high voltagedifferences.
Electrons are conducted away from the inside of atelevision screen.
Photocopiers work because positively charged toner isattracted to paper.
6 Arrange the following in order of charge passed, starting withthe lowest.
A current of 2 A in a circuit for 5 minutes.
6 kJ of energy is transferred between two points with a voltagedifference of 12 V.
A current in a 3 Ω resistor with a voltage difference of 6 Vbetween its ends for 7 minutes.
A current of 10 A in a circuit for 30 s.
© Heinemann Educational 2001 145
Physics TB7 Self-assessment TB7 Higher
I O NI O NI O NI O NI O N
current = charge time
energy = current × voltage
power = power × time
voltage = work done charge passed
TM ?
Using electricity1 All of the answers end in ION.
Which ION causes charging by rubbing?
Which ION makes unlike charges move together?
Which ION makes like charges move apart?
Which ION allows electrons to move through a metal?
Which ION causes opposite charges by contact?
2 Rearrange the letters in this anagram to make shocking piece ofequipment.
RAT OF FEARED VEGAN GRAN VAN DE GRAAFF GENERATOR3 Which two wires are connected to the ground either at the
house or at the power station? Put rings around the correctanswers.
earth fuse live neutral
4 Draw a straight line between the boxes to complete theequations. Write the correct unit in the box next to thequantity.
5 True or false?
It is important to connect an aircraft to its tankerbefore refuelling. T
Oil tankers are filled with hydrogen gas before cleaningto avoid explosions. F
Air can become a conductor between high voltagedifferences. T
Electrons are conducted away from the inside of atelevision screen. T
Photocopiers work because positively charged toner isattracted to paper. F
6 Arrange the following in order of charge passed, starting withthe lowest.
A current of 2 A in a circuit for 5 minutes. – 36 kJ of energy is transferred between two points with a voltagedifference of 12 V. – 2A current in a 3 Ω resistor with a voltage difference of 6 Vbetween its ends for 7 minutes. – 4A current of 10 A in a circuit for 30 s. – 1
© Heinemann Educational 2001
Physics TB7 Self-assessment answers TB7 Higher
146
I TCRF I O NA TCTA RT I O NU SLR PE I O NU TCOC DN I O NU TCI DN I O N
current = charge timeampenergy = current × voltagejoule / kilowatt-hourpower = power × timewatt / kilowattvoltage = work done charge passedvolt
AM ?
Electromagnetism1 Solve the clues and fill in the squares with electromagnetic words.
Find the name of a scientist.
1 He worked onelectromagnetism.
2 An electromagnetic sounddevice.
3 An a.c. producer.4 Reverses current in a motor.5 National carrier of electricity.6 The process of producing a
current from a changingmagnetic field.
7 A current producer.
2 Rearrange the letters in this anagram to make a larger voltage.
ROSE – START FERN PUMP
3 Which two are renewable energy sources used to produceelectricity? Put rings around the correct answers.
coal oil Sun water
4 Finish this sentence.
The input coil of a transformer is known as the _ _ _ _ _ _ _ coil
and the output coil is known as the _ _ _ _ _ _ _ _ _ coil.
5 True or false?
Fleming’s left hand rule works for motors.
A motor spins faster if the current is smaller.
A motor spins faster if the magnetic field is stronger.
Reversing the current and field directions will reversethe motor direction.
If a d.c. motor is spun by hand, a direct current isproduced.
6 Draw a straight line between the boxes to match each fingerwith the correct physical quantity for Fleming’s left hand rule.
© Heinemann Educational 2001 147
Physics TB8 Self-assessment TB8 Foundation
1
2
3
4
5
6
7
First finger
Second finger
Thumb
Current direction
Force on wire
Magnetic field direction
TTM ?
Electromagnetism1 Solve the clues and fill in the squares with electromagnetic words.
Find the name of a scientist. FLEMING1 He worked on
electromagnetism.2 An electromagnetic sound
device.3 An a.c. producer.4 Reverses current in a motor.5 National carrier of electricity.6 The process of producing a
current from a changingmagnetic field.
7 A current producer.
2 Rearrange the letters in this anagram to make a larger voltage.
ROSE – START FERN PUMP STEP-UP TRANSFORMER3 Which two are renewable energy sources used to produce
electricity? Put rings around the correct answers.
coal oil Sun water
4 Finish this sentence.
The input coil of a transformer is known as the
primary coil and the output coil is known as the
secondary coil.
5 True or false?
Fleming’s left hand rule works for motors. T
A motor spins faster if the current is smaller. F
A motor spins faster if the magnetic field is stronger. T
Reversing the current and field directions will reversethe motor direction. F
If a d.c. motor is spun by hand, a direct current isproduced. T
6 Draw a straight line between the boxes to match each fingerwith the correct physical quantity for Fleming’s left hand rule.
© Heinemann Educational 2001
Physics TB8 Self-assessment answers TB8 Foundation
148
1
2
3
4
5
6
LACG
AN
RORO
O
EITC
TORI
T
RMDDE
NU
U
K E RAEPSDO UYADAA
EMING
LF R
N
AT A T
RR
T O
7
First finger
Second finger
Thumb
Current direction
Force on wire
Magnetic field direction
AM ?
Electromagnetism1 Solve the clues and fill in the squares with transformer words.
1 This one increases voltage.2 See 10.3 The input side.4 The output side.5 This one decreases voltage.6 A changing magnetic one makes it work.7 Two of these, one each side.8 Direct will not work. This will.9 Thin sheeted core.10 and 2 These cause the core to heat up.11 With 100% efficiency, this is the same at
both input and output.
2 Rearrange the letters in this anagram tomake two opposite electromagneticdevices.
NOT MY DOOR MA
3 Finish this sentence.
The part of the motor which reverses the current direction is
known as the _ _ _ _ _ _ _ _ _ _.
4 True or false?
An a.c. generator has slip rings.
If a generator is turned faster, the size of the inducedcurrent increases.
If a generator is turned faster, the frequency of thecurrent decreases.
Large generators have moving magnets and fixed coils.
Mutual induction is the induction of an opposingvoltage in the same coil.
5 Arrange the following transformers in order of output voltage,starting with the lowest.
No. of input turns Input in V No. of output turns
500 230 500
5000 230 250
50 12 1000
2000 12 500
200 24 100
© Heinemann Educational 2001 149
Physics TB8 Self-assessment TB8 Higher
TR
O
ANSF
1
2
M9
3
R11
4
R8
5
7
6
E10
TM ?
Electromagnetism1 Solve the clues and fill in the squares with transformer words.
1 This one increases voltage.2 See 10.3 The input side.4 The output side.5 This one decreases voltage.6 A changing magnetic one makes it work.7 Two of these, one each side.8 Direct will not work. This will.9 Thin sheeted core.10 and 2 These cause the core to heat up.11 With 100% efficiency, this is the same at
both input and output.
2 Rearrange the letters in this anagram tomake two opposite electromagneticdevices.
NOT MY DOOR MA
MOTOR DYNAMO3 Finish this sentence.
The part of the motor which reverses the current direction is
known as the commutator.
4 True or false?
An a.c. generator has slip rings. T
If a generator is turned faster, the size of the inducedcurrent increases. T
If a generator is turned faster, the frequency of thecurrent decreases. F
Large generators have moving magnets and fixed coils. T
Mutual induction is the induction of an opposingvoltage in the same coil. F
5 Arrange the following transformers in order of output voltage,starting with the lowest.
No. of input turns Input in V No. of output turns
500 230 500 4
5000 230 250 2
50 12 1000 5
2000 12 500 1
200 24 100 3
© Heinemann Educational 2001
Physics TB8 Self-assessment answers TB8 Higher
150
TC U R R
ES P U PE N T SY
R Y
O
A RMIRPOCES N D A
S T E DP O NW
N GD
I E DLI L S
F
1
2
L A M I N A T E9
3
REWOP11
C
4
T IETLA R N A8
5
7
6
D D YE10
AM ?
Electronics and control1 Solve the clues and fill in the
squares with electronic componentsand devices.
1 See 9.2 Output 1 if either input 1.3 Digital computational device.4 Opposite output to input.5 Temperature sensitive component.6 Flip flop.7 AND and not.8 Two NORS with feedback.9 and 1 Combinations of electronic
switches.10 Switches high current with low.
2 Draw a straight line between the boxes to join each logic gatewith its symbol and truth table.
in out
0 0 0AND 0 1 0
1 0 01 1 1
in out
0 0 0NAND 0 1 1
1 0 11 1 1
in out
0 0 1NOR 0 1 1
1 0 11 1 0
in out
0 0 1OR 0 1 0
1 0 01 1 0
3 True or false?
A potential divider uses two resistors to split a currentin a circuit.
LDRs and thermistors can be used in potential dividerarrangements.
A relay is used because the output current from a logicgate is too small.
Two NOR gates can be combined to make an ANDgate.
© Heinemann Educational 2001 151
Physics TBA1 Self-assessment TBA1 Higher
1
2
3
4
5
6
7
8
9
10
TTM ?
Electronics and control1 Solve the clues and fill in the
squares with electronic componentsand devices.
1 See 9.2 Output 1 if either input 1.3 Digital computational device.4 Opposite output to input.5 Temperature sensitive component.6 Flip flop.7 AND and not.8 Two nors with feedback.9 and 1 Combinations of electronic
switches.10 Switches high current with low.
2 Draw a straight line between the boxes to join each logic gatewith its symbol and truth table.
in out
0 0 0AND 0 1 0
1 0 01 1 1
in out
0 0 0NAND 0 1 1
1 0 11 1 1
in out
0 0 1NOR 0 1 1
1 0 11 1 0
in out
0 0 1OR 0 1 0
1 0 01 1 0
3 True or false?
A potential divider uses two resistors to split a currentin a circuit. F
LDRs and thermistors can be used in potential dividerarrangements. T
A relay is used because the output current from a logicgate is too small. T
Two NOR gates can be combined to make an ANDgate. F
© Heinemann Educational 2001
Physics TBA1 Self-assessment answers TBA1 Higher
152
1
2
3
4
5
6
7
8
9
10
TG AROUPMOC E RT
R MEHCDN
GO CIYAL
S T O RI
S TI B L EA
TONHTTALANBLER
E S
AM ?
Processing waves1 Solve the clues and fill in the squares with resonant phenomena.
1 Resonance at the natural one. 2 Type of vibration.3 Wave which appears not to move. 4 A multiple.5 Maximum amplitude. 6 How a particular note sounds.7 Main. 8 External vibration.
9 Zero amplitude.
2 Rearrange the letters in this anagram to make two oppositeelectromagnetic devices.
I FACED NEXT RIVER3 True or false?
All colours of light have the same refractive index forwater.
Constructive interference occurs when waves are inphase.
Beats occur if notes are always out of phase.
Open pipes have antinodes at both ends.
Interference can be explained by thinking of light as aparticle.
4 Draw four lines from each object position to the correct imageproperties and position.
object position image position / property
between lens and f
between lens and f between f and 2f
at 2f
beyond 2f
between f and 2f same side of lens as object
real
virtual
at 2f magnified
diminished
same size
beyond 2f upright
inverted
© Heinemann Educational 2001 153
Physics TBA2 Self-assessment TBA2 Higher
R1
E2
4
5
6
7
SONAN
8 C9 E
3
TTM ?
Processing waves1 Solve the clues and fill in the squares with resonant phenomena.
1 Resonance at the natural one. 2 Type of vibration.3 Wave which appears not to move. 4 A multiple.5 Maximum amplitude. 6 How a particular note sounds.7 Main. 8 External vibration.
9 Zero amplitude.
2 Rearrange the letters in this anagram to make two oppositeelectromagnetic devices.
I FACED NEXT RIVER REFRACTIVE INDEX3 True or false?
All colours of light have the same refractive index forwater. F
Constructive interference occurs when waves are inphase. T
Beats occur if notes are always out of phase. F
Open pipes have antinodes at both ends. T
Interference can be explained by thinking of light as aparticle. F
4 Draw four lines from each object position to the correct imageproperties and position.
object position image position / property
between lens and f
between lens and f between f and 2f
at 2f
beyond 2f
between f and 2f same side of lens as object
real
virtual
at 2f magnified
diminished
same size
beyond 2f upright
inverted
Physics TBA2 Self-assessment answers TBA2 Higher
© Heinemann Educational 2001154
R1
E2
4
5
6
7
SONAN
EFM O
OQF
NITMAUU
8 COF R9 EON D
TN
LD
AI C
I T YA
E D
T I O N
D E
A R
M E N T A L
YH A R
DQ U E YN C
3
AM ?
More about forces and energy
1 Solve the clues and fill in the squares with the mechanical words.
1 To move backwards.2 Measured in Ns.3 A thrown body.4 and 7 Works by Newton
III (three words).5 Path described by 3.6 Forward force.7 See 4.
2 Rearrange the letters in this anagram to make two things arocket needs to carry into space.
YOUNG EX-ELF
3 Finish this sentence.
The amount of energy required to change the temperature of
unit mass of a substance by one degree is called the
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ of the substance.
4 Equations true or false?
momentum = mass × velocity
impulse = velocity / time
force = momentum change / time
u + at = √(u2 + 2as)
½ (u + v)t = ut + ½ at2
5 Arrange the following in order of energy requirement starting with thesmallest.
Energy needed to raise the temperature of 0.5 kg of water (s.h.c. 4200 J/kgoC)by 25oC.
Energy supplied to the element of a 230 V, 3 kW kettle heater in twominutes.
Energy supplied to the 40% efficient lift motor which lifts 500 N to a heightof 60 m in 1minute.
6 Isaac and Helen are standing at the top of a 50 m high cliff. They have twosimilar sized stones.
Helen drops her stone at the same time as Isaac throws his as hard as he canhorizontally away from the cliff.
Which stone hits the beach first. Put a ring around the correct answer.
Both stones together Helen’s stone Isaac’s stone
© Heinemann Educational 2001 155
Physics TBA3 Self-assessment TBA3 Higher
I1
M2
4
5
6
7
PULSE
3
TTM ?
More about forces and energy1 Solve the clues and fill in the squares with the mechanical words.
1 To move backwards.2 Measured in Ns.3 A thrown body.4 and 7 Works by Newton
III (three words).5 Path described by 3.6 Forward force.7 See 4.
2 Rearrange the letters in this anagram to make two things arocket needs to carry into space.
YOUNG EX-ELF OXYGEN FUEL3 Finish this sentence.
The amount of energy required to change the temperature of
unit mass of a substance by one degree is called the
specific heat capacity of the substance.
4 Equations true or false?
momentum = mass × velocity T
impulse = velocity / time F
force = momentum change / time T
u + at = √(u2 + 2as) T
½ (u + v)t = ut + ½ at2T
5 Arrange the following in order of energy requirement starting with thesmallest.Energy needed to raise the temperature of 0.5 kg of water (s.h.c. 4200 J/kgoC)by 25oC. – 1Energy supplied to the element of a 230 V, 3 kW kettle heater in twominutes. – 3Energy supplied to the 40% efficient lift motor which lifts 500 N to a heightof 60 m in 1minute. – 2
6 Isaac and Helen are standing at the top of a 50 m high cliff. They have twosimilar sized stones.Helen drops her stone at the same time as Isaac throws his as hard as he canhorizontally away from the cliff.Which stone hits the beach first. Put a ring around the correct answer.
Both stones together Helen’s stone Isaac’s stone
© Heinemann Educational 2001156
Physics TBA3 Self-assessment answers TBA3 Higher
I1
M2
4
5
6
7
PULSE
LRM E
AT
E
RA AT
PUN
RR
TN
OB I
G
J E C TN E
N T U M
B OH R
I L
I
EJ E T
OE C O
3
AM ?
TB1 Electric circuits
The following circuit symbols are very important:
Electricity is a flow of charged particles called electrons. This flow ofcharged particles is called electrical current. The circuit must be completefor this to happen. A switch enables the circuit to be broken in order tostop the electric current. Current is measured in amps (A) using anammeter. The ammeter should be connected in series with othercomponents in the circuit. Current is not used up by the components inthe circuit.
A cell or battery provides an electric current that will travel around acircuit. It transforms chemical energy into electrical energy. A battery issimply a number of cells connected together with the poles pointing in thesame direction.
There are two basic types of circuit, series and parallel. Series circuits haveall the components arranged one after the other on a single loop of thecircuit (see Fig 1). The lamps in a series circuit will be dimmer and if onelamp ‘burns out’ the others will not light either. In a series circuit, thecurrent is the same in all parts of the circuit. However, the cell or batterieswill last longer. An example of a series circuit is a set of Christmas treelights.
A parallel circuit has its components connected on separate loops of thecircuit (see Fig 2). The lamps in this type of circuit will be brighter and ifone lamp ‘burns out’ the others will stay lit. In a parallel circuit, thecurrent in the main branch is the sum of the currents in the side branches.However, the cells or batteries will not last as long. An example of aparallel circuit is the ring main in a house.
Wires will oppose the flow of current in a circuit, and this is calledresistance. It is this resistance that causes wires to heat up. A variableresistor or dimmer can alter the resistance in a circuit, allowing more orless current to pass through.
Nerves in the body are rather like electrical circuits, carrying messagesaround the body from the brain and spinal cord.
© Heinemann Educational 2001 157
Key Stage 3 Summary sheet
orswitch cell or
lamp
battery
ammeterwire
variable resistor
A
Fig 1
Fig 2
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TB2 Forces and energy
All forces do three things: change the shape of an object, change its speed, orchange its direction. Forces are measured in newtons (N), using a forcemeter.An object that is standing still will have balanced forces on it.
Upthrust is the upward force from water that keeps things afloat. Whether anobject will float or not depends on its density. A dense object will have particlesthat are very close together, it is likely to sink. Objects with a density less thanwater will float. An object weighed in water will weigh less than in air. This isbecause of upthrust.
Mass is the amount of matter that makes up an object. It is measured in gramsand kilograms. Weight is the force of gravity pulling on a mass. Weight is aforce and so is measured in newtons. On Earth, each kilogram of mass weighs10 newtons.
Friction is the force that opposes motion and is caused by surfaces rubbingtogether. Friction can be useful or it can be a nuisance. Adding a lubricant, likeoil or grease, to the working parts of machines can reduce friction. They reducefriction by smoothing out the rough surfaces.
It is the frictional forces that make a car stop. The faster a car is travelling, thelonger its stopping distance will be.
Temperature is a measure of how hot things are. In science, the Celsius scale(°C) is used. Temperature is measured using a thermometer.
Heat is a form of energy. If an object absorbs heat energy, then its temperaturewill rise. If it loses heat energy, then its temperature will fall.
A material that will allow heat energy to flow through it more easily is called agood thermal conductor, e.g. metals. A material that is a poor thermalconductor will allow heat energy to flow less easily, e.g. wool, polystyrene, andrubber. Liquids and gases are also poor thermal conductors. Poor thermalconductors are called insulators. Energy flow through a material is calledconduction. Conduction is the transfer of heat energy from particle to particleby vibration.
Trapped air is a particularly good insulator. This method of insulation is usedin duvet fillings, expanded polystyrene, and loft insulation. Trapped air stopsenergy being lost by convection. Convection relies on air being able to flow andtrapped air cannot, so convection stops. Energy costs money and so insulatorsare used throughout homes in an effort to reduce unwanted energy transfer,e.g. double glazing, draught excluders, heavy curtains, carpets.
When objects get hotter they get bigger. This is called expansion. For example,roads are often made of concrete slabs. On a hot day they will expand, sobetween the slabs are expansion gaps filled with a soft material, which allowsthe slabs to expand easily.
Liquids and gases are called fluids because they can flow. When liquids andgases expand the particles get further apart, and this causes a decrease indensity. When this happens the hot, less dense fluids will rise to be replaced bycooler, denser fluids. This is called convection current.
Whilst conduction and convection both need particles to carry energy, thermalradiation does not. Thermal radiation is part of the electromagnetic spectrum.In particular, the part called infrared. This is the only type of energy transferthat can occur in a vacuum. Heat and light from the Sun travels as infraredradiation through the vacuum of space.
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Solids, liquids and gases are all states of matter. They can change from onestate to another if heat energy is given or taken away. These changes arereversible.
In order to calculate the speed of an object, the distance it has travelled and thetime taken must be known. Usually the speed calculated is an average speed,because over a journey, a moving object, e.g., a car, will change its speed atvarious points. Speed is measured in metres/second (m/s) or kilometres/second(km/s). The process of increasing speed is called accelerating and slowing downis decelerating.
speed =distance
time
Objects move as the result of exerting a force upon them. A force can alsoproduce a change in speed. In general, the larger the force, the greater the effect itwill have on speed. The forward force is called thrust and the opposing force iscaused by the frictional effect from the surface and air resistance, often referredto as drag. These are called the horizontal forces. If thrust and drag are balancedthen the object will move at a constant speed. The vertical forces are weight andupthrust. When forces are balanced then there will be no change in speed.
Air and water resistance increase with increasing speed. Therefore, if the resistingforce increases, then the energy required to move the object forward at a greaterspeed will be more. For example, the fuel consumption of a car will increase withincreasing speed. Streamlining can reduce the effects of air resistance or waterresistance. Streamlining is where the shape of the moving object (car, boat, plane)is modified so that the fluid (air, water) flows over it smoothly and this will enablethe object to move faster without the need to increase thrust.
Air resistance is a form of friction, which is caused by two surfaces rubbingtogether. When this happens, heat is produced. If air resistance increases withincreasing speed, then at very high speeds the air resistance can lead to heating.
With falling objects, the two main forces are air resistance and weight. As anobject falls, weight remains the same, but air resistance will increase as theobject accelerates. Eventually, as the object falls, the forces of air resistance andweight will balance and the object will fall at a constant speed.
Pressure depends on two things, the amount of force exerted and the area overwhich it is distributed. Pressure is measured in newtons/metre2 (N/m2) ornewtons/cm2 (N/cm2). Practical examples of this effect are everywhere.For example, a sharp blade will have the force spread over a small area, so thepressure will be great, and this will make it better for cutting. pressure =
forcearea
Gases and liquids can also be under pressure. Pneumatics is the practicalapplication of gases under pressure, hydraulics is the practical application ofliquids under pressure. Because there are many empty spaces between gasparticles, they can be compressed, e.g. make the particles come closer togetherby using a force. However, there are no spaces between liquid particles so theyare incompressible; this makes them excellent at transmitting the forcethroughout the liquid.
Atmospheric or, underwater pressure at a particular point depends on theweight of fluid above.
A lever is a simple machine which uses a pivot. Machines can be either used asforce multipliers (crowbar or wheelbarrow), or as distance multipliers (arm orfishing rod). If a smaller effort force is exerted than the load force, then thelever will be a force magnifier. The further away the effort force is from thepivot, then the more the force is magnified. Because there is a pivot involvedthe force will have what is known as a turning effect or moment or torque.Moments are measured in newton metres (Nm). Levers are found in manyeveryday objects, such as scissors and tin openers. Arms and legs are also levers.
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TB3 Wave properties
Light travels from a luminous source. Light is a wave. A luminous objectis one that gives off its own light, including stars, candles, light bulbs,lasers etc. Light travels much faster than sound. The speed of light is300 000 km/s and it takes about 8.5 seconds to travel from the Sun to theEarth. We can see non-luminous objects because light is reflected off theminto our eyes.
Light travels in straight lines. It does not bend around objects. In science,drawing rays can represent the path of light. A beam of light is several raystravelling together.
Light cannot bend around opaque objects. However, the direction of lightcan be changed in two ways. One is by reflection and the other is byrefraction. Refraction is where the light changes direction at the boundarybetween two different media, e.g. as it travels from air into glass or water.
All sounds begin with an initial vibration. Sound is a wave. For example,the strings of a guitar vibrate to produce sound. Sounds can be high or low,loud or quiet, hard or soft. How high or low a sound is refers to its pitch orfrequency. Loud or soft refers to a sound’s intensity, and loud or quietrefers to the sound’s quality. A ‘picture’ of a sound wave can be seen if asignal generator is connected to an oscilloscope.
The height of a wave indicates how loud it will be. The higher the wavethe louder the sound. The height of a wave is referred to as the wave’samplitude.
Sound waves need a medium to travel through. They can travel throughsolids, liquids and gases, but they do so at different speeds. Sound travelsfastest through solids (5000 m/s through iron) and slowest through gases(330 m/s through air). Sound travels faster through solids because they aredenser than gases and liquids. The particles are closer together and so passon the vibrations more efficiently. Sound cannot travel through a vacuumbecause there are no particles to vibrate.
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TB4 Using waves
When light hits an object, the result will depend on the material of theobject, which can be transparent, translucent or opaque. Transparentobjects will allow most of the light to be transmitted through them.Translucent objects will allow less transmission and opaque objects willallow no transmission of light. The light that is not transmitted may beabsorbed or reflected.
When light is reflected from a plane (flat) surface, its path can be predicted.The light is reflected from a surface at the same angle at which it hits it.This is the Law of Reflection. Reflections are very useful in everyday life, forexample, in mirrors, reflective clothing and periscopes.
When light is reflected from a plane surface, for example, a mirror, animage is formed. The image is formed as far behind the mirror as the objectis in front. It is upright but it is laterally inverted. Laterally inverted meansthat right is left and left is right. The image formed in a plane mirror isvirtual. Virtual means that the image cannot be formed on a screen.
If white light is passed through a prism at the right angle, it can bedispersed into seven different colours, which are called the visiblespectrum (red, orange, yellow, green, blue, indigo, and violet).
Coloured filters will transmit their own colour, but will absorb all theother colours of the spectrum. For example, a green filter will allow greenlight through but will absorb all other colours. The primary colours of lightare red, green and blue. When they are all mixed together, they form whitelight. Mixing any two together will form a new colour. For example,mixing red and blue light together will form magenta.
A coloured object in white light will reflect its own colour and absorb all othercolours. Black is complete absorption of light by an object. For example, a redobject in green light will appear black because it will absorb the green light.
Pitch or frequency of sound can be altered in several ways. For example, astringed instrument will produce a sound of higher pitch if the string isshortened, tightened, or made lighter. Wind instruments will produce asound of higher pitch if the pipe is shorter. A drum will produce a sound ofhigher pitch if the skin is tightened. These actions all have the effect ofincreasing the speed of the vibration, e.g. a higher frequency of vibration.
All animals do not hear the same range of frequencies of sound. Someanimals can detect sounds that are inaudible (can’t be heard) to human ears.For example, humans cannot hear a dog whistle or hear the ultrasonic beepssent out by bats to find their location. In fact, different people will heardifferent ranges of pitch and these ranges will change as people age.The typical range of hearing for an adult human is from 20 Hz to 20 000 Hz.
Sound waves are picked up by the ear and travel into the ear canal to theeardrum, which vibrates. This causes the small bones to vibrate and thevibration is passed to the inner ear, where the vibrations are converted intoelectrical signals and translated by the brain into sounds.
Any sound that is unpleasant is referred to as noise. When this noise is frequentor carries on all day (like airport noise), it is referred to as noise pollution. Noiselevels can be measured using a sound-level meter in units called decibels (dB).Workers in very noisy factories may have to wear ear defenders to protect theirears from the noise. These act as sound insulators. Loud noise can permanentlyaffect hearing by damaging the sensitive nerve endings in the inner ear.
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TB5 Radioactivity
There are no KS3 statements on radioactivity. You will, however, need toknow something about atomic structure before you start to studyradioactivity.
You may have done this in Chemistry.
All substances are made up from about 100 elements.
These elements are made up from very tiny particles called atoms.
A piece of copper is made up from copper atoms and a piece of carbon ismade up from carbon atoms. Atoms are made up from different numbers ofthree particles – protons, neutrons and electrons. Protons have a mass ofone atomic mass unit (a.m.u.) and a single positive charge. Electrons havenegligible mass and a single negative charge. Neutrons have a mass of onea.m.u. but no charge.
As all atoms are neutral, they must contain equal numbers of protons andelectrons.
An atom contains protons and neutrons packed together in a positivelycharged nucleus. Electrons move around the nucleus in certain energylevels or shells. Each energy level can contain a maximum number ofelectrons.
E.g. A sodium-23 atom contains 11 protons, 11 electrons and 12 neutrons.The protons and neutrons are packed together in the nucleus. Theelectrons are arranged in three energy levels – two in the first energy level,eight in the second energy level and one in the third energy level.
It is possible to get different atoms of the same element. These mustcontain the same number of protons and electrons but different numbers ofneutrons. These different atoms are called isotopes.
E.g. A carbon-12 atom has 6 protons, 6 neutrons and 6 electrons. Acarbon-14 atom has 6 protons, 8 neutrons and 6 electrons.
Radioactivity involves changes in the nucleus of an atom.
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TB6 The Earth and Universe
A day is the time it takes for a planet to make one complete rotation on itsaxis. For Earth this is 24 hours. In daytime the Earth is facing the Sun and atnight it is facing away. A year is the time taken for a planet to make onecomplete orbit around the Sun, 365 days for the Earth. The Moon is a naturalsatellite of the Earth, which means that it is in orbit around the Earth. A monthis the time taken for the Moon to go through all of its phases (or shapes). Thesephases are always in the same order. A lunar month is 28 days long.
The Sun is our local star. A star is a luminous object, which means that it givesoff its own light. Moons and planets are non-luminous. The Sun’s lightilluminates them and they can be seen by this reflected light.
Eclipses only happen when the Sun, the Earth and the Moon are all in a line.There are two types, the lunar eclipse and the solar eclipse. A lunar eclipse isan eclipse of the Moon. It happens when the Earth is positioned between theSun and the Moon. Because the Moon is so much smaller than the Earth, theEarth will cast a shadow over the Moon and it will be in darkness. A solareclipse is an eclipse of the Sun. This time the Moon will cast a shadow over theEarth, but because it is so much smaller than the Earth, only a relatively smallpart of the Earth is in darkness.
The seasons are caused by the tilt of the Earth on its axis, which is 23.5°. Insummer, the Earth is tilted towards the Sun, giving warmer, longer days and theSun appears to be high in the sky. In winter, the Earth is tilted away from theSun, giving colder, shorter days and the Sun always appears to be low in the sky.
The Sun, together with all the planets, asteroids and their satellites in orbitaround it make up the Solar System. Within our solar system, only the Earth isknown to support any life forms because the conditions are right, e.g. the righttemperature, oxygen present, water present. The planets are kept in orbit bygravitational forces. The orbits of the planets are not exactly circular, but theyare ellipses or oval shaped.
Looking from Earth, the stars appear to be moving. However, this is because ofthe Earth’s rotation. The stars can only be seen at night because the Sun iscloser and is therefore much brighter. A collection of stars in a pattern is calleda constellation. Many millions of stars clustered together are called a galaxy.All the galaxies put together form the universe.
Gravity is an attractive force which acts on the Earth towards the centre of theplanet. The greater the mass of an object, the greater will be its gravitationalforce. It is the force of gravity acting upon the mass of an object that gives itweight. This means that say, on the Moon, which has a lesser mass than Earth,the gravitational force will be less and therefore objects will weigh less.Gravitational force between objects also decreases as the distance betweenthem increases. For example, to enable a rocket to get off the ground a thrustforce is needed that is greater than the rocket’s weight, but once in space,further away from the gravitational force, less thrust is needed.
Early models of the solar system put the Earth at the centre, with the Sun andother planets orbiting around it (Ptolemy). However, Copernicus discoveredthat it is actually the Sun that is at the centre, and that the Earth and otherplanets orbit around it. The Sun is the most massive object in our solar systemand therefore it has the most gravity, which keeps all the planets in orbitaround it. Compared to the Moon, the Earth is more massive and it is theEarth’s gravity that keeps the Moon in orbit around it. The Moon is said to be anatural satellite of the Earth.
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TB7 Using electricity
Fuses are deliberate weak links in a circuit, designed to melt if there is toobig a current. They melt because the electrical energy from the battery istransformed into heat and light. They are used to protect appliances from alarge and possibly damaging current. For this reason it is important alwaysto use the correct fuse for the job. Household fuses have been replaced byelectromagnetic circuit breakers, which are resettable when they ‘trip’ out.
Electricity can be dangerous. Mains electricity (which comes to homes) has ahigh voltage (230 V). This is a much greater voltage than can be supplied frombatteries. For this reason, electrical appliances should not be handled with wethands, wires should not be frayed or objects inserted into plug sockets.Electricity can cause severe burns or electrocution if these hazards are ignored.
Energy can be taken in many forms and can be routinely converted fromone form into another. Some examples are potential energy (stored energy),kinetic energy (movement energy), sound energy, solar (light) energy,thermal (heat) energy, chemical energy and electrical energy, to mentionbut a few. Electrical energy is used so widely because it is easily convertedinto other types by energy changing devices, e.g. a kettle convertselectrical energy into heat energy.
The electrical energy in a circuit can be transformed (converted) in thecomponents, e.g. to produce light, sound, movement, etc. Cells andbatteries store chemical energy which is converted into electrical energy.Electrical energy cannot be stored easily.
Voltmeters are used to measure voltage (also known as potentialdifference) in the circuit. The measurements can be for certaincomponents in the circuit, which, if added together, will give the totalvoltage of the cell or battery. These measurements indicate how muchenergy is being transferred by a component.
The National Grid system transfers energy from the power station to thehome at high voltages but low current. This is less wasteful. Transformerscan easily change the voltage to suit requirements.
In the home, electrical current is conducted from ‘the mains’ to componentsin electrical circuits and these convert the energy into other useful forms.Circuits that are involved in heating (kettles, electric fires), will transferenergy at a greater rate than others (hi-fi systems, computers). The rate ofenergy transfer is known as power and is measured in watts (W). Mainselectricity is supplied by a generator back at the power station. A variety ofenergy resources can be used to generate electricity such as nuclear, fossilfuels, and renewable energy sources such as wave or wind power.
The major problem with using fossil fuels as energy resources is that theyproduce pollution and contribute to the Greenhouse Effect, whilst nuclearpower stations produce dangerous and difficult to deal with waste.However, renewable sources, although ‘clean’, have other problems.For instance, wind turbines are unsightly and noisy, building dams forhydroelectric power can affect the ecology and are not viable in flat areas.
In any energy transfer, there is a transfer to useful energy and ‘wasted’energy. This wasted energy is said to have been dissipated or spread outand cannot be used again. This wasted energy is usually heat energy.For example, in a coal burning power station a great deal of energy(about 70%) is wasted in the boiler or in the cooling water.
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TB8 Electromagnetism
Magnets will attract magnetic materials – iron, cobalt, and nickel.All other metals cannot be magnetised. A compound called magnetic ironoxide can also be magnetised. This is not a metal but is used in ceramicmagnets. Magnets have north-seeking and south-seeking poles. Like polesof magnets will repel, unlike poles of magnets will attract. Magnetic forceswill act through non-magnetic materials. For example, a fridge magnet willattract the steel door of the fridge even though a piece of paper is inbetween.
Magnetic materials can be made into magnets in several ways. One way isto ‘stroke’ the material with the pole of another magnet in the samedirection. This lines up the magnetic domains of the material being‘stroked’.
A magnetic field is the area in which a magnetic force can be felt orexperienced. The magnetic field of a magnet can be shown by using ironfilings and has a distinctive shape. When magnetic fields are drawn, fieldline patterns are used. The field lines are closer together at the poleswhich tells us that the poles are where the magnetic field is strongest.The further away from the magnet you go, the weaker the magnetic fieldbecomes. The direction of a magnetic field can be plotted using compassesand this can be shown by arrows on the magnetic field lines.
The Earth has a magnetic field. A compass needle is simply a free-movingmagnet that will line up with the Earth’s magnetic field. In order for acompass needle to point north, the point at which it is suspended, thepivot must be almost free of friction and air resistance.
When an electric current is passed down a wire, a magnetic field isproduced around it. The magnetic field can be made stronger by wrapping acoil of wire around a ‘soft’ iron core. Magnetically ‘soft’ means that theiron can be both magnetised and demagnetised easily. This type of magnetis called an electromagnet. The field can be made even stronger by usingmore coils of wire or a larger current. If the iron bar is made into ahorseshoe shape, the field will be stronger because the poles are closertogether. The magnetic field around an electromagnet is the same shape asthat of a bar magnet.
Because the core is magnetically ’soft’, it will become magnetised onlywhen there is a current flowing in the coil. This makes an electromagnetvery useful in picking things up and putting them down when needed.Electromagnets are found in scrapyards to pick cars up and in electric bellsand relays.
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Electric circuits
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 identify cells, batteries and generators as electrical sources, and bulbs, resistors, bells,motors, LEDs and buzzers as parts of an electrical circuit where electrical energy isdissipated.
recognise the electrical symbols for a cell, battery, power supply, filament bulb, switch,LDR, fixed and variable resistor, LED, motor, heater, ammeter and voltmeter should beknown.
2 recall that resistors are heated when electric current passes through them.
3 describe the effect of a variable resistor in controlling the brightness of a lamp and thespeed of a motor.
explain the effect of a variable resistor in controlling the brightness of a lamp and thespeed of a motor.
4 measure resistance by correctly placing a voltmeter and an ammeter in a circuit.
5 state the equation V = IR.
use the equation V = IR
6 describe how current varies with voltage in a metal wire at constant temperature.
describe how current varies with voltage in a filament bulb.
describe how current varies with voltage in a silicon diode.
7 describe how the resistance of an LDR varies with light level.
8 describe how the resistance of a thermistor varies with temperature.
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Forces and energy
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
Force and Rotation
1 explain how the turning effect of a force depends on the size of the force and theperpendicular distance from the point of application to the pivot.
2 state the equation moment of a force = force × perpendicular distance to pivot.
use this equation.
3 use, for a balanced system, the equation
sum of clockwise moments = sum of anticlockwise moments.
Force and Energy
4 state the equation work done = force × distance moved in its own direction.
use this equation.
5 use the equation power = work done (or energy transfer) / time taken.
6 use the equation
change in gravitationalpotential energy
massgra
= vitational
field strengthheight moved.
7 state the equation kinetic energy = 12 mv2.
use this equation.
8 state the equation energy transferred = work done.
use this equation
9 use the equation
energy efficiency =useful energy output
total energy input
10 explain the meaning of the term energy efficiency in the heating of buildings.
explain the meaning of the term energy efficiency in the performance of machines.
11 describe how domestic insulation reduces energy transfer by conduction, convection andradiation.
12 use data on energy efficiency measures to evaluate cost-effectiveness of differentapproaches.
Force and Motion
13 state the equation speed = distance / time taken.
use this equation.
14 plot and interpret distance–time graphs.
15 calculate speed from a distance–time graph.
16 plot and interpret speed time–graphs.
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17 calculate distance travelled from a speed–time graph.
18 describe how braking distance is affected by the road surface, the mass and speed of thevehicle.
19 describe factors that affect the “thinking distance”.
20 recall that stopping distance is the sum of the thinking distance and the braking distance.
21 use the equation, energy transferred = force × distance = 12 mv2.
to discuss stopping distances.
22 recall that velocity describes the speed and direction of a moving object.
23 calculate velocity from a displacement–time graph.
24 state the equation, acceleration =change in velocity
time taken.
use this equation.
25 calculate acceleration from a velocity–time graph.
26 describe the relative sizes of the horizontal forces on an object moving in a straight linewhen it is accelerating.
describe the relative sizes of the horizontal forces on an object moving in a straight linewhen it is decelerating.
describe the relative sizes of the horizontal forces on an object moving in a straight linewhen it is moving at constant speed.
27 state the equation force = mass × acceleration.
use this equation.
28 apply this relationship to the action of seat-belts and crumple zones.
29 describe forces acting between objects.
30 recognise that when object A pulls or pushes object B then object B pulls or pushesobject A with an equal-sized force in the opposite direction.
Forces on falling objects
31 describe the effects of the Earth’s pull and resistive forces due to motion in a fluid.
32 use the equation: weight = mass × gravitational field strength.
33 explain how the size of the resistive force depends on the speed of the object.
34 describe how the forces acting on an object falling at terminal velocity are balanced.
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Wave properties
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 describe the effects of absorbing electromagnetic waves: heating, ionisation and damageto cells and tissue.
2 explain that wave motion involves an oscillation.
3 describe the differences between a transverse and a longitudinal wave.
give an example of a transverse wave.
give an example of a longitudinal wave.
4 recall the meaning of the term frequency.
recall the meaning of the term wavelength.
recall the meaning of the term amplitude.
5 identify the wavelength transverse wave.
identify the amplitude of a transverse wave.
6 describe the effect on the loudness of a sound when the amplitude is changed.
7 describe the effect on the pitch of a sound when the frequency is changed.
8 state the equation, wave speed = frequency × wavelength.
use this equation.
9 describe how echoes are caused by the reflection of sound.
10 recall that refraction involves the change in speed of a wave.
11 explain how changing the speed of a wave causes a change in wavelength.
explain how changing the speed of a wave may cause it to change direction.
12 explain and illustrate how virtual images are caused by the refraction of light.
13 recall that water waves can be reflected at a plane barrier.
recall that the angle of incidence equals the angle of reflection.
14 explain and illustrate how plane waves are reflected at a concave barrier.
explain how circular ripples are reflected at a plane barrier.
15 recall that water waves can be refracted if they are slowed down.
16 recall that water waves can spread out at a narrow gap.
recall that this is known as diffraction.
17 describe how the amount of spreading depends on the size of the gap compared to thewavelength of the wave.
18 recall that light can be diffracted but needs a very small gap as the wavelength of light isvery small.
19 appreciate that the diffraction of light is evidence for the wave nature of light.
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20 explain that sound can be diffracted.
21 describe how the amount of diffraction of sound depends on the size of the sound source.
describe how the amount of diffraction of sound depends on the wavelength of the sound.
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Using waves
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
The Electromagnetic Spectrum
1 recall that the different types of electromagnetic waves form a continuous spectrum witha range of wavelength and frequency and that they transfer energy at the same speed infree space.
2 list the parts of the spectrum in order of wavelength and frequency (gamma rays; X-rays;ultraviolet; light; infra-red; microwaves; radio waves).
3 recall that microwaves cause heating when absorbed by water.
recall that microwaves cause burns when absorbed by body tissue.
4 recall that infra-red radiation causes heating when absorbed by any object, and its use inradiant heaters.
5 recall that ultra-violet radiation is produced in fluorescent lights.
6 recall that being out in the Sun for too long can cause sunburn and skin cancer from theultra-violet radiation.
7 explain that the darker the skin, the more ultra-violet radiation is absorbed by the skinand less reaches the deeper body tissues to cause these cells to become cancerous.
8 describe how information can be transmitted using electromagnetic radiation, includingthe use of satellites for global communication.
9 explain that radio waves are readily diffracted and are therefore suitable for broadcasting.
10 explain how information in narrow beams can be transmitted using microwaves.
11 describe the use of infra-red radiation in night photography.
12 describe what happens to light incident on a perspex/glass-air surface both above andbelow the critical angle of incidence.
13 describe how light is reflected at the inner face of a right-angled prism.
14 explain how optical fibres are used in endoscopy.
15 explain how optical fibres allow the rapid transmission of data using digital signals.
16 describe the transmission of data pulses using light in optical fibres.
17 describe the difference between analogue and digital signals.
18 describe the advantage of using digital signals to allow more information to betransmitted.
19 explain that X-rays pass through flesh but are absorbed by bone.
20 list the safety precautions that should be taken when using X-rays and gamma-rays.
21 interpret information about the development of ideas concerning the dangers involvedwith using X-rays and/or radioactive substances from given information.
22 describe the use of gamma-rays as tracers to detect malfunction of organs and astreatment for killing body tissue.
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23 recall that ultrasound is a high-frequency longitudinal wave.
24 explain how distances can be measured using echo-sounding.
25 explain how the reflection of ultrasound by body tissue enables organs to be scanned.
26 describe how ultrasound is used for pre-natal scanning.
27 describe one non-medical use of ultrasound.
Seismic Waves
28 recall that earthquakes produce shock waves, that affect the surface of the Earth andtravel inside the Earth.
recall that these shock waves can be detected by instruments (seismometers) located onthe Earth’s surface.
29 recall that during earthquakes, P-waves (primary waves) are formed.
recall that P-waves are longitudinal waves which travel through both solids and liquids.
recall that S-waves (secondary waves) are formed.
recall that S-waves are transverse waves which travel through solids but not throughliquids.
recall that P-waves travel faster than S-waves.
30 explain how the differences in behaviour of P-waves and S-waves inside the Earth can beinterpreted in terms of a simple mantle/core structure for the inner Earth.
31 explain how the seismographic record can be used to find the speed of seismic waves,which give evidence for the structure of the Earth.
32 describe the composition of the Earth’s outermost layer in terms of plates in relativemotion.
recall that new plate material is formed at mid-ocean ridges where sea-floor spreadingoccurs.
recall that plates collide at subduction zones where the oceanic lithosphere descendsbelow the continental lithosphere, forming off-shore trenches and parallel volcanicmountain chains.
recall that plates slide past each other at transform fault zones.
recall that the forces at the plate boundaries contribute to the rock cycle.
recall that sea floor spreading causes fractures (cracks) which are filled with molten rockfrom below the lithosphere (new rock is produced).
recall that at subduction zones, increased temperature and pressure can causemetamorphism.
recall that metamorphism produces new rocks by recrystallisation (no melting occurs).
recall that descending lithosphere enters the hot mantle and partially melts to formmagma.
recall that rising magma can crystallise deep below the surface to form coarse-grainedrocks (e.g. granite) or rise to the surface in volcanoes to form fine-grained rocks (e.g. basaltlava or volcanic ash).
33 interpret given information about developments in ideas of plate tectonics from giveninformation.
© Heinemann Educational 2001
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Radioactivity
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 describe how the breakdown of an unstable nucleus results in radioactive emission andthe formation of a new element.
2 explain that a stable nucleus can become unstable by the absorption of neutrons.
3 explain that the level of background radiation, from a variety of sources, is higher in someplaces than in others.
4 describe how to take background radioactivity into account when performingexperiments.
5 recall the relative penetration of alpha, beta and gamma emissions.
6 apply this knowledge to explain why different emissions are suited to particular purposesto include sterilisation, thickness measurement, treatment of cancer, tracer techniques.
7 describe alpha, beta and gamma in terms of atomic particles and electromagnetic waves.
8 explain that the activity of a radioactive sample decreases with time.
9 attribute this decrease in activity to a corresponding decrease in the number of unstablenuclei.
10 explain half-life as the average time for the number of undecayed nuclei in a sample tohalve.
11 explain that different radioactive materials decay at different rates.
12 use an activity–time graph to determine the half-life of a material.
13 describe how the half-life of a material can be measured.
14 apply an understanding of half-life to explain why different sources are suited toparticular purposes.
15 explain how measurements of the amounts of radioactive elements and their decayproducts in rocks can be used to calculate the age of a rock.
16 interpret given information about developments in ideas of radioactivity from giveninformation.
17 recall that exposure to ionising radiation can be harmful.
18 describe the precautions that should be taken when handling radioactive materials.
19 describe some effects of radiation on the human body.
20 explain how the effects of radiation depend on the energy and penetration of the emissionas well as the amount of exposure.
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Physics TB5 Student checklist
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The Earth and Universe
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 recall the names and properties of bodies in the Universe:
the planets in the Solar System
comets
meteors
stars, galaxies and natural satellites.
2 explain that the orbit time of a planet depends on its distance from the Sun.
3 explain that the Moon remains in orbit around the Earth, and the planets orbit the Sun,because of the gravitational attractive forces between them.
4 interpret given information about developments in ideas about models of the SolarSystem.
5 explain that the orbit period of an artificial satellite increases with increasing heightabove the Earth’s surface.
6 describe the variation in gravitational force with distance.
7 explain the variation in speed of a comet during its orbit around the Sun.
8 describe how stars evolve over a long timescale:fusion, red giant, white dwarf, supernova, neutron star, black hole.
9 explain that theories for the origin of the Universe must take into account that
light from other galaxies is shifted to the red end of the spectrum
the further away galaxies are, the greater the red shift.
10 recognise that one way of explaining this is that
other galaxies are moving away from us very quickly
galaxies furthest from us are moving fastest.
11 explain how knowledge of the rate of expansion of the Universe enables its age to beestimated.
12 explain that there are possible futures for the Universe depending on the amount of massin the Universe and the speed at which the galaxies are moving apart.
13 interpret given information about developments in ideas of the origin of the Universe.
14 discuss how scientists are trying to find evidence of life on other planets in the SolarSystem and elsewhere in the Universe.
© Heinemann Educational 2001
Physics TB6 Student checklist
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Using electricity
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
Electrostatic Phenomena
1 explain that when two objects rub together and become charged, electrons are transferredfrom one object to the other.
2 explain how charging by contact and charging by induction occur in terms of themovement of electrons.
3 recall that there are repulsive forces between objects with similar charges, and attractiveforces between objects with opposite charges.
Uses of Electrostatics
4 describe some everyday beneficial uses of electrostatic charge to include photocopying,ink-jet printers and the removal of ash from the waste gases in a coal-burning powerstation and where it should be avoided to include on the inner surface of a televisionscreen and when refuelling aircraft.
Electrostatics and Current
5 recall that current is a flow of charge.
6 state and be able to use the equation:
charge = current × time.
7 explain that the current in a metal is due to a flow of electrons from negative to positive.
explain that a current in an electrolytic solution is due to a flow of both positively andnegatively charged particles.
8 recall that the voltage between two points is the number of joules of energy transferredfor each coulomb of charge that passes between the points.
Electricity in the Home
9 state and be able to use the equation
power = voltage × current.
10 explain that a direct current is always in the same direction, but an alternating currentchanges direction.
11 recall that energy is supplied to houses through the live wire and neutral wires.
12 recall that in normal use no current passes in the earth wire.
13 explain that the live wire has to be insulated from the earth and neutral wires.
14 explain how fuses and circuit breakers prevent fire due to electrical faults.
15 explain how the earth wire, together with the fuse or circuit breaker, preventselectrocution.
16 explain why double-insulated appliances do not need an earth wire.
17 explain that energy can be transferred from the electricity supply as convection currentsand also as electromagnetic waves, including infra-red and microwaves.
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Physics TB7 Student checklist
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I can: A B
18 use the equation:
energy = power × time
to calculate energy transfer in joules and kilowatt-hours.
19 recall that a domestic electricity meter measures the energy transfer in kilowatt-hours.
20 calculate the cost of electrical energy from a knowledge of the power, the time and theunit cost.
© Heinemann Educational 2001
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Electromagnetism
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 recall that a current-carrying conductor at right angles to a magnetic field experiences aforce.
2 describe the effect of reversing the current and the direction of the magnetic field.
3 explain how this effect is used in a simple electric motor.
4 describe the effect of changing the size of the current and the strength of the magneticfield.
5 explain how the forces on a current-carrying coil in a magnetic field produce a turningeffect on the coil.
6 describe the use of a split-ring commutator in a simple d.c. motor.
7 recall that a voltage is induced in a conductor when it moves across a magnetic field.
8 recall that a voltage is induced in a conductor when the magnetic field through itchanges.
9 describe how the size of the induced voltage depends on the rate at which the changeoccurs.
10 recall the effect of reversing the change.
11 explain that an alternating current is generated when a magnet rotates within a coil ofwire.
12 explain that a changing magnetic field in one coil of wire can induce a voltage in aneighbouring coil.
13 explain that a transformer changes the size of an alternating voltage.
14 describe the construction of a transformer as two coils of wire wound on an iron core.
15 describe the difference in action and in construction of a step-up and a step-downtransformer.
16 state and be able to use the equationVp / Vs = Np / Ns.
17 state and be able to use the equationVp Ip = Vs Is.
18 describe the energy flow through a coal-burning power station.
19 discuss the social and environmental issues associated with different methods ofgenerating electricity.
20 explain that electricity is generated by rotating an electromagnet within coils of wire.
21 describe power losses in transmission.
22 explain why power is transmitted at high voltage.
23 describe the use of transformers in power transmission.
24 explain why the use of transformers dictates the use of alternating current.
© Heinemann Educational 2001 177
Physics TB8 Student checklist
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Electronics and control
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 recall that the input signal for a logic gate is either a high voltage (about 5 V) or a lowvoltage (about 0 V).
2 recall that the output of a logic gate is high or low depending on its input signals.
3 recall the truth tables of AND, OR, and NOT gates in terms of high and low signals.
4 recall how to use switches, LDRs and thermistors in series with resistors to provide inputsignals for logic gates.
5 explain how an LED and series resistor can be used to indicate the output of a logic gate.
6 recall that a relay is needed for a logic gate to switch a current in a mains circuit becausea logic gate output cannot supply much power.
recall that a relay is needed for a logic gate to switch a current in a mains circuit becausethe relay isolates the low voltage gate from the high-voltage mains.
7 recall that relays controlled by logic gates can be used to switch currents in circuitscontaining heaters, motors, lights and locks.
8 explain how logic gates are used as part of an electronic system consisting of input,processor and output device.
9 identify input, processor and output stages of an electronic system from a circuit diagramemploying logic gates.
10 recall how to work out the truth table of a logic system with up to three inputs madefrom logic gates.
11 recall how to assemble a circuit of logic gates which obeys a given truth table of up toeight rows.
12 recall the truth tables of NAND and NOR gates.
13 recall how to connect NOR and NAND gates to make a latch (bistable) circuit.
14 explain how, for a NOR and NAND gate latch, a brief high signal at one input results in apermanent high signal at the latch output.
explain how, for a NOR and NAND gate latch, a brief high signal at the other inputcauses a low signal at the latch output.
explain how, for a NOR and NAND gate latch, a low signal at both inputs leaves the latchoutput signal unchanged
15 explain how two resistors can be used as a potential divider.
16 explain how one fixed resistor and one variable resistor in a potential divider allowsvariation of the output voltage.
17 explain how to calculate the output signal of a potential divider from the values of its resistors.
18 explain how a thermistor and an LDR can be used with a fixed resistor to generate asignal for a logic gate which depends on environmental conditions.
19 explain how a thermistor and an LDR can be used with a variable resistor to provide asignal with an adjustable threshold for a logic gate.
Physics TBA1 Student checklist
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Processing waves
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 use the equation:
refractive index =speed of light in vacuumspeed of light in medium
2 recall that dispersion occurs because waves of different wavelength travel at differentspeeds in transparent materials.
3 explain dispersion in terms of refractive index.
4 describe the effect of a convex lens on a diverging beam of light.
describe the effect of a convex lens on a parallel beam of light.
5 recall that light incident on a convex lens parallel to the axis passes through the focalpoint after passing through the lens.
6 recall how to find the position and size of the real image formed by a convex lens bydrawing rays from the object which pass through the centre of the lens.
recall how to find the position and size of the real image formed by a convex lens bydrawing rays from the object which moves parallel to the axis before the lens and passthrough the focal point after passing through the lens.
7 describe the use of a convex lens as a magnifying glass.
describe the use of a convex lens in a camera.
describe the use of a convex lens in a projector.
8 explain how a camera is focused.
explain how a projector is focused.
9 recall that all objects vibrate with a characteristic, or natural, frequency.
10 recall that the natural frequency of an object increases with decreasing mass.
11 recall that resonance occurs when an object is subjected to a vibration at its naturalfrequency.
12 describe the effects of resonance in a pendulum.
describe the effects of resonance in a mass on a spring.
describe the effects of resonance in a vibrating string.
describe the effects of resonance in a column of air in a musical instrument.
13 recall that a musical instrument produces a sound when a column of air vibrates at itsnatural frequency.
recall that a musical instrument produces a sound when a string vibrates at its naturalfrequency.
14 recall that the natural frequency of a column of air decreases with increasing length ofthe column.
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Physics TBA2 Student checklist
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I can: A B
15 describe qualitatively how the natural frequency of a vibrating string depends on itslength, mass and tension.
16 recall that a string can vibrate in different modes, each with a different number of nodes.
17 recall that the frequency of a vibrating string increases with increasing number of nodes.
18 appreciate that the quality of the note from a stringed instrument depends on the relativeintensity of the modes of vibration.
19 use the displacement–time graph of a sound wave to determine its frequency.
use the displacement–time graph of a sound wave to determine its amplitude.
use the displacement–time graph of a sound wave to determine its quality.
20 recall that interference effects can be observed in sound waves.
recall that interference effects can be observed in surface water waves.
recall that interference effects can be observed in electromagnetic waves.
21 recall that interference of two waves results in a pattern of reinforcement andcancellation of the waves.
22 describe a demonstration of interference using sound, water waves or microwaves.
23 explain interference effects in terms of constructive and destructive interference.
24 recall that the number of half-wavelengths in the path difference for two waves from thesame source is an odd number for destructive interference.
recall that the number of half-wavelengths in the path difference for two waves from thesame source is an even number for constructive interference.
25 interpret the developments in ideas about the nature of light from given information.
© Heinemann Educational 2001
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More about forces and energy
Tick column A when you have covered the statement in class.
Tick column B when you are confident you can answer any questions on it.
In your revision for your end-of-block test or final examinations, concentrate most time on thosestatements not ticked.
Statements in bold can only appear on the Higher Tier paper.
I can: A B
1 recall that an acceleration preceded by a minus sign represents a deceleration.
2 calculate acceleration and displacement from a velocity–time graph.
3 recall the equations v = u + at , v2 = u2 + 2as and s = ut + 12 at2.
use these equations.
4 recall that an object projected horizontally in the Earth’s gravitational field, in theabsence of friction, has a constant horizontal velocity.
recall that an object projected horizontally in the Earth’s gravitational field, in theabsence of friction, has a steadily increasing vertical velocity.
5 describe the path of an object projected horizontally in the Earth’s gravitational field.
6 recall the equation: momentum = mass velocity.
use this equation.
7 recall that momentum is conserved.
8 apply the principle of momentum conservation to the interaction of two objects movingin one dimension.
9 explain that there is a force on a rocket from its exhaust gases.
10 recall that rockets carry their own supply of fuel and oxygen.
11 recall that injuries in vehicle collisions are due to very rapid accelerations of parts of thebody.
12 explain that spreading acceleration over a longer time reduces the forces which act.
13 recall the use of crumple zones, air-bags and safety straps in cars.
14 recall the equation:
energy transfer = mass specific heat capacity temperature change.
use the equation.
appreciate some of the effects of materials having different specific heat capacities.
15 describe ways in which energy transfer from a house is reduced.
16 appreciate that in many processes energy is ultimately dissipated as heat in thesurroundings.
17 classify energy sources as renewable or non-renewable.
18 evaluate the advantages and disadvantages of geothermal, wind, fossil fuel, nuclear andbiomass as sources of energy.
19 describe how energy from renewable and non-renewable sources can be transferred to auseful output.
20 evaluate the efficiencies of energy transfer devices by comparing energy input and usefulenergy output.
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Physics TBA3 Student checklist
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I can: A B
21 recall the equation:
efficiency =useful work or energy output
total energy input.
use this equation.
© Heinemann Educational 2001
Physics TBA3 Student checklist
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Electric circuits
Introduction spread
In-text questions
(a) A cells : lamps = 2:1 C cells : lamps = 1:2 (ratio = 1:1 in B).(b) A. Largest cell : lamps ratio so largest current. (Brightest lamp must
have greatest current.)(c) Ammeter. Amperes/amps/A.(d) Voltmeter. Volts/V.(e) Good conductors – e.g. copper, brass, iron etc. (metals)
Bad conductors – e.g. wood, paper, plastic etc.(f) One cell with two lamps in parallel.(g) Advantage: e.g. minimum amount of connecting wire needed/lamps
all in one long line so easier to arrange; voltage is shared so lots of lowvoltage lamps can be used (e.g. 20 × 12 V lamps, 40 × 6 V etc.)Disadvantage: e.g. one loose or broken lamp means none of themwork.
(h) Two lamps, each with a switch, connected in parallel.(i) A1 = A2 = 2 A.(j) X. If both switches were closed the lamp would be short-circuited.
Spread 1.1
In-text questions
(a) Sound energy (+ some thermal energy).(b) P off, Q off; R on, S off.
Thinking further questions
1 Place a resistor in series with the LED. 2 The resistor becomes hotter.
There are more and/or faster electrons to collide with the resistor’s atomsso more KE is transferred. Atoms of resistor vibrate more, so resistorbecomes hotter.
3 Two LED’s in parallel but facing in opposite directions, in series with thepower supply.Two LED’s ensures that the circuit is working as one LED is always lit.
4 High melting point, good electrical conductor, ductile.
Spread 1.2
In-text questions
(a) P = 2 A Q = 1 A R = 3 A.(b) V1 = 4 V V2 = 8 V.(c) 0 V.(d) V = IR = 3 × 8 = 24 V.
Thinking further questions
1 12 V 6 Ω 0.25 A. 2 (a) 0.5 A current through battery = 1.5 A.
(b) VA = VB = 6 V VC = 12 V.
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3 12 V battery with starter motor, lights and wipers connected in parallel,each with a switch. Starter motor needs a large current so the lamps haveless current, hence they are dimmer.
4 (a) Supply with two lamps in parallel; the dimmer one has a resistor inseries with it.
(b) As in (a) but the resistor is replaced by a variable resistor.
Spread 1.3
In-text questions
(a) Keep current/supply voltage low; switch on only to take readings.(b) Filament gets very hot so resistance does not remain constant/
resistance increases.(c) Current values read from graph.
At 2 V I = 0.26 A R = 2/0.26 = 7.7 ohmsAt 4 V I = 0.34 A R = 4/0.34 = 11.8 ohmsAt 6 V I = 0.40 A R = 6/0.40 = 15.0 ohmsResistance increases as voltage increases.
(d) Thermistor – more electrons released so current increases andresistance decreases. Metal wire – greater lattice vibrations soresistance increases and current decreases.
(e) More free electrons per unit length so current greater and resistancesmaller.
Thinking further questions
1 Curved graph as in fig 16.Similar shaped curve, from (0, 0), but above original curve.
2 At low voltage there is a very high resistance, then the resistance decreasessuddenly and becomes very small, leading to a rapid rise in current.When voltage is reversed there is no current so the resistance becomesextremely large.
3 Resistance of LDR increases in the dark so the current decreases. Hencethe milliammeter reading will decrease.
4 (a) When first switched on the filament is cold so has a low resistanceand therefore the current is high (I = V/R).
(b) The cold thermistor has a high resistance so keeps the current low atfirst. As the filament and the thermistor heat up, the filamentresistance increases and the thermistor resistance decreases.
5 Power supply, resistor and LED (with arrow on symbol pointing in thesame direction as the current), all in series.Voltage across resistor = 10 V. R = V/I = 10/0.020 = 500 ohms.
Physics TB1 Answers in-text and Thinking further
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Electric circuits
Answers
1 thermal, light, amperes, ammeter, series, voltage, voltmeter, parallel, voltage, current, ohms. 11
2 Circuit. 3Voltmeter reading = 3 V. 1
3 (a) Axes scaled; axes labelled – quantity and unit; plots;straight line. 4
(b) Resistance is constant; resistance = 10 ohms (approx.) from gradient of graph or byaveraging values calculated from table. 2
(c) (i) 0.19–0.21 A (ii) 6.2–6.3 V. 2
4 (a) X – ammeter; 2 A. 2
(b) Y – voltmeter; 8 V. 2
(c) M = V/I = 4/2 = 2 ohms; N = 8/2 = 4 ohms. 4
5 (i) S open – both equally bright/normal brightness; same current in each lamp.(ii) S closed – A out; B brighter than before; S closed gives lower resistance path for
current/short circuit/lamp shorted; less resistance so bigger current in circuit(so B brighter). 6
6 (a) R = V/I = 2.5/3 = 8.3 ohms. 3
(b) (i) supply, lamp, variable resistor, ammeter in series, voltmeter in parallel across lamp. 3
(ii) I–V graph as Figure 16.
As current increases there are more free electrons to collide with the atoms/ions in thefilament; more KE transferred/vibrations increase; the temperature/resistance of thefilament increases. 5
(c) 6 V power supply, lamp and resistor in seriesR = (6 – 2.5)/0.3 = 3.5/0.3 = 11.7 ohms. 5
7 (a) Fog lamp is in series with the headlamps; so voltage is shared; and current is lessthan normal. 3
(b) Fog lamp now short-circuited. 1
(c) Circuit – fog lamp and switch in parallel with car battery. 3
8 (a) Ammeter reading increases; resistance of LDR is low in the light; so current(I = V/R) increases. 3
(b) Current too small/resistance in circuit too large; increase voltage of power supply. 2
9 (a) 170 ± 10 ohms. 1
(b) Temperature when R = 100 ohms = 55°C; temperature when R = 250 ohms = 12°C;temperature change = 55 – 12 = 43°C. 3
(c) Low temperatures; graph steepest here. 2
(d) Controlling temperature of any process up to (say) 20°C. 1
10 (a) If a metal is cooled, its atoms vibrate less; offering less obstruction to the electrons. 2
(b) No resistance to current; so no energy wasted as heat. 2
(c) Temperature below which a material becomes superconducting. 1
(d) It only occurred at extremely low temperatures; materials with higher criticaltemperatures are now available. 2
(e) Magnetic resonance imaging. 1
(f) Virtually no friction; so it could go faster/use less fuel. 2
(g) No expensive/bulky cooling equipment needed; process would be very efficient as noenergy would be wasted as heat. 2
(h) Long cables could transfer energy without loss/power transmission lines/thinnerwires could be used/avoid use of expensive cooling systems. 1
Physics TB1 Answers: end of teaching block
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Forces and energy
Introduction spread
In-text questions
(a) Change the shape/size/speed/direction of motion of an object. (Any 3)(b) Newton (N).(c) Average speed = 800 m/40 s = 20 m/s.(d) 10 N.(e) 20 N.(f) Friction force is less so car’s tyres do not grip the road as well.(g) 2 m from pivot on RHS/1 m from right hand end.(h) gravitational potential energy; changes to kinetic energy.(i) Temperature is the degree of hotness of an object; heat is the quantity
of thermal energy it possesses so depends on the mass and material ofthe object as well as its temperature.
(j) conduction, convection, radiation, evaporation.
Spread 2.1
In-text questions
(a) Moment of force = 200 N × 0.15 m = 30 Nm.(b) Moment of Priya = 400 N × 2 m = 800 Nm.(c) Moment of Dan = 500 N × 2 m = 1000 Nm.(d) Anticlockwise.(e) Dan could move closer to the pivot
Priya could hold something weighing 100 NThey could move the pivot towards DanAnother person could sit on Priya’s side.
(f) F × 1 m = 800 N × 0.4 m F = 320 N.(g) Diagrams showing pivot and applied force each time. Explanation to
include the principle of moments so that a small force a large distancefrom the pivot can lift a large force close to the pivot.
Thinking further questions
1 Long spanner. The force is applied at a greater distance from the nut (pivot) so the force is less toprovide the same moment.
2 (a) No effect as his moment about the pivot is zero.(b) Seesaw will go down on the LHS.
3 (a) Taking moments about B: FA × 80 m = 120 kN × 50 m FA = 75 kN.(b) Force at B = 120 – 75 = 45 kNAssumed that the weight of the bridge is negligible compared with theweight of the lorry so can be ignored.(c) Graph of FA against distance from A – straight line changing from F =
120 kN at A to 0 kN at B. 4 Pivot the metre rule at its centre of mass. Put the 1 N weight at one end.
Place the block on the other side of the pivot and adjust its position untilthe rule balances. Note its distance from the pivot. Use the principle ofmoments to calculate a value for the weight of the block.(a) Use a larger weight than 1 N; for example, a 10 or 12 N weight.(b) A tiny movement of the weights makes the rule unbalanced.
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Spread 2.2
In-text questions
(a) It is an average speed because it is impossible to keep the speedconstant all the time.
(b) Average speed = 2000 m/356.24 s = 5.614 m/s.(c) Speed = 20/8 = 2.5 m/s(d) Gradient is increasing in (b) and decreasing in (c).(e) Speed after 4 s = gradient of tangent at t = 4 s = (approx.) 23/6.6 =
3.5 m/s(f) Speed after 2 s = gradient of tangent at t = 2 s = (approx.) 28/6.6 =
4.2 m/sSpeed after 4 s = gradient of tangent at t = 4 s = (approx.) 25/8.0 =3.1 m/sSpeed decreases as time increases.
(g) In fig 20 distance travelled = ½ × 6 × 10 = 30 m.In fig 21 distance travelled = 30 m.
Thinking further questions
1 Average speed = 12/0.33 = 36 km/hTime = 12/48 = 0.25 hours or 15 minutes.
2 Graph.(a) Uniform speed of 20 m/s for 5 s, stopped for 3 s, uniform speed of
30 m/s for 2 s.(b) Average speed = 160/10 = 16 m/s.
3 (a) Graph.(b) Average speed = 130/2.5 = 52 km/h.(c) Line on graph starting at t = 9.00 am when distance from Luton = 130
km and reaching 0 km at 10.30 am with no horizontal sections.Two cars pass where graphs cross. Estimate because table only givesthe distance from Luton every 30 minutes. (Car could have stopped orspeed changed during each 30 minute interval.) Answer for second carwill depend on how the graph is drawn.
Spread 2.3
In-text questions
(a) OA constant velocity of 3.3 m/sAB constant velocity of 5 m/s in opposite direction, back to starting
pointBC constant velocity of 5 m/s on opposite side of starting pointCD constant velocity of 2.5 m/s in opposite direction, back tostarting point.
(b) Graph with increasing and decreasing gradients.(c) 90 km/h = 90/3.6 = 25 m/s.
Thinking further questions
1 (a) 0 (b) 50 m/s (c) 0. 2 (a) 36.1 m/s (b) 1188 km/h. 3 Graph
(a) distance travelled = sum of areas above and below the time axis= 32 km.
(b) displacement = 0 since areas above and below the time axis are equal. 4 (a) 1885 s.
(b) 0.40 m/s.
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Physics TB2 Answers in-text and Thinking further
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Spread 2.4
In-text questions
(a) acceleration = (12 – 8)/4 = 1 m/s2.(b) OA constant acceleration of 5 m/s2 from rest
AB constant deceleration of 5 m/s2 to stop at BBC constant acceleration of 2.5 m/s2 in opposite directionCD constant deceleration of 2.5 m/s2 to stop at D
Object does not return to its starting point because the areas OAB andBCD are not equal.
Thinking further questions
1 Speed is constant but direction is changing; therefore cyclist isaccelerating.
2 130 km/h = 36(.1) m/s, acceleration = 36/12 = 3 m/s2. 3 velocity – time graph.
(a) Acceleration = 20/16 = 1.25 m/s2.(b) Retardation = 20/40 = 0.5 m/s2.(c) Distance travelled = ½ (60 + 116) × 20 = 1760 m.
4 Constant retardation of 5/0.5 = 10 m/s2 followed by constant accelerationof 10 m/s2 in the opposite direction. It returns to its starting point as thetotal displacement (area under graph) is zero.The graph could represent a ball thrown vertically upwards at 5 m/s.
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In-text questions
(a) Jo will move backwards.(b) The planets are attracted to the Sun (gravitational attraction). The Sun
is much more massive than the planets so they orbit the Sun at such adistance and velocity that they are in equilibrium.
(c) mass (i) weight on Earth (ii) weight on Moon45 kg 450 N 75 N100 g 1 N 0.16 N1 kg 10 N 1.6 N
Thinking further questions
1 (a) by lubrication/oiling.(b) E.g. walking/car wheels turning/car brakes.
2 (a) 720 N.(b) 1440 N.(c) 72 kg.
3 The chair is pushing up on Amy with a force of 450 N. 4 Electrostatic force of attraction between the positively charged nucleus
and the negatively charged electrons. Electron mass is much smaller thanthe mass of the nucleus so the electrons orbit the nucleus (in the same wayas the planets orbit the Sun).
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In-text questions
(a) Accelerates (i) to right (ii) up (iii) to left and down (iv) to rightand up.
(b) To reduce air resistance enabling them to go faster.(c) To reduce air resistance enabling them to go faster.
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Thinking further questions
1 Diagram showing A weight down, B lift up, C thrust forwards, D dragbackwards.Length of arrows for A = B and C = D.(a) accelerates (b) decelerates (c) lift force must increase.
2 200 N Box slows down. 3 Constant velocity. 4 (a) 7 × 106 N.
(b) The resultant force will increase due to (a) mass decreasing as fuel isused up, (b) g decreasing as height increases.
(c) Its acceleration increases. 5 (a) Speed is constant so there is no resultant force; therefore the tension
in the tow-bar equals the forward thrust.(b) 400 N(c) Tension in tow rope = 400 N
resistance to motion = 400 Nweight = 10 000 Nnormal reaction force = 10 000 N.
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In-text questions
(a) As the mass (and hence weight) of the trolley changes, the force downthe ramp will change. The angle of the slope must be changed so thatthe force down the slope is equal to the friction force once more.
(b) a against 1/m. Graph would be a straight line through the origin.(c) 60 N.(d) The force is in the opposite direction to the direction of motion.(e) For a given force and mass F = ma fixes the acceleration.
Acceleration = change in velocity/time so the longer the time thegreater the velocity change produced.
Thinking further questions
1 5 m/s2. 2 3 m/s2. 3 To give the maximum acceleration. 4 2.5 m/s2.
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In-text questions
(a) 1500 J.(b) 1500 J.(c) Paul’s power = 1500/20 = 75 W; Pat’s power = 1500/60 = 25 W.(d) GPE = 9 J.(e) WD = 9 J (same as answer to (d)).(f) KE gained = GPE lost = 9 J.(g) 6 m/s.(h) GPE = 4.5 J KE = 4.5 J.
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Thinking further questions
1 90 000 J. 2 (a) weight = 500 N (b) WD = 150 000 J (c) Power = 167 W. 3 (a) 720 N (b) 120 N (c) 0 N. 4 Darren’s KE = 4320 J; Meera’s KE = 2160 J – this is half of Darren’s KE. 5 (a) GPE = 3500 J (b) 10 m/s.
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In-text questions
(a) (i) 7 m (ii) 21 m (iii) Graph – straight line through the origin ofgradient 0.7.
(b) Braking distance increases with mass and speed as the vehicle hasmore energy to lose in stopping. (H level students may see that it isproportional to mass and to (speed)2 by reference to KE = 1/2 mv2 butthis comes later in the text.)Good brakes and good grip reduce the braking distance as bothincrease the friction force.
(c) 5000 N.(d) 54 m.(e) Thinking distance = 14 m as before but braking distance = 80 m
(doubles). Stopping distance becomes 94 m.(f) Larger mass means larger braking distance (they are proportional) so
stopping distance increases. If speed increases too, the brakingdistance is proportional to (speed)2 so increases even more rapidly.More KE to lose means more damage done in the event of an accident.
Thinking further questions
1 speed thinking braking stopping(m/s) distance (m) distance (m) distance (m)
15 9 20 2920 12 35 4725 15 55 7030 18 80 98
Thinking distance goes up by 3 each time but the braking distance andstopping distance increase much more rapidly. When speed doubles thebraking distance quadruples.
2 Thinking distance = 40 m compared with a ‘normal’ value of 12 m.Stopping distance will be much greater. Reference to values in table in Q1.
3 Smooth tread has less friction so the braking distance will increase. Treadalso prevents aquaplaning in wet weather; this also reduces friction withthe road and increases the braking distance.
4 KE = 112 500 J. Braking force = 112 500/20 = 5625 N.
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In-text questions
(a) A ping-pong ball weighs less so the air resistance force will equal theweight at a lower speed than for a golf ball. This means that terminalvelocity is reached at a lower height for the ping-pong ball.
(b) As the resistive force is greater, it will equal the weight at a lowerspeed and so more quickly. The terminal velocity is therefore less.
(c) 600 N.
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(d) Upright position means the air resistance force is less so she will bemoving faster before the forces on her become balanced. Therefore herterminal velocity will be greater.
(e) Speed – time graph. Acceleration of 10 m/s2 at first, decreasinggradually until terminal velocity is reached. When parachute opensthere is a rapid deceleration to a new, much lower, terminal velocityuntil the parachutist is brought to rest on hitting the ground.
Thinking further questions
1 Use light gates to measure the velocity of the marble at 10 cm intervals asit falls/the time taken to fall successive 10 cm intervals. If it reachesterminal velocity the velocity/time will become constant.
2 Graph. Linear up to d = 80 cm (approx.) then air resistance force becomessignificant so acceleration decreases and the rate of increase of b alsodecreases.
3 weight = mg F = ma becomes mg = ma therefore a = g = 10 m/ss near theEarth’s surface.
4 m = 0.1 kg is falling at a constant speed (a = 0) as the air resistance forceequals its weight.m = 1 kg has an acceleration of 9 m/s2. Its speed is increasing but the valueof its acceleration will gradually decrease as the air resistance forcecontinues to increase.
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In-text questions
(a) Hardly any free electrons.(b) Hot water rises.(c) The atoms have fixed lattice positions so cannot move around.(d) Heat is transferred through the metal wall of the radiator by
conduction; this heats the air adjacent to the radiator, setting up aconvection current which gradually heats the whole room. There is alittle radiation from the hot metal wall of the radiator but the mainmethod of heat transfer is convection.
(e) insulation cost annual saving pay-back timecavity wall insulation £600 £30 20 yearsdouble glazing £3000 £60 50 yearsdraught-proofing £40 £20 2 yearsloft insulation £400 £80 5 yearsjacket for hot water tank £15 £15 1 yearjacket for hot water tank.
Thinking further questions
1 Colder, denser air sinks and warmer air rises, to be cooled by the freezercompartment, so cooling the whole of the fridge by convection.
2 To provide a fresh supply of oxygen, avoiding risk of suffocation. 3 Terraced house has fewer outside walls so energy loss through the walls
is less. 4 loft insulation – conduction
carpets and curtains – conductiondouble glazing – conductioncavity wall insulation – conduction and conventiondraught proofing – convectionlagging of hot water tank – conduction and radiation.
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5 Thermostats to control the temperature of each room/turn down thethermostat temperature/do not heat all the rooms/have the heating on forless time each day/wear warmer clothing.
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In-text questions
(a) lubrication.(b) 8%.(c) (i) 15 W (ii) 60%.(d) 40%.(e) walls – 2000 W floor – 600 W windows – 1500 W.(f) 6600 W.(g) ordinary – 35% CHP – 80%.
Thinking further questions
1 10 000 MW 2 (a) 30% (b) transferred to heat and some sound 3 26.7% 4 Cavity wall insulation/double glazing/small windows/thick carpets and
curtains/hot water tank and pipes well insulated/loft insulation/draughtproofing/solar panels in roof/grass roof.
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Forces and energy
Answers
1 mass, kilograms, weight, gravity, newtons, mass, weight, energy, joules, gravitationalpotential, kinetic, efficient, heat, sound. 14
2 clockwise = anticlockwise moments; 1x = 0.9 × 0.2; x = 0.18 m (18 cm) from pivot – from12 cm mark on rule. 5
Diagram.
3 (a) A = lift; B = thrust; C = weight; D = drag. 4
(b) A = C; B = D. 2
(c) A, B and D increase. C is unchanged (ignoring change in g). 4
4 (a) E.g. Walking/car wheels turning/car brakes. 2
(b) Energy is transferred to heat energy. 2
5 (a) GPE, KE. 2
(b) GPE increases, KE stays the same. 2
(c) 1000 N. 1
6 (a) (i) GPE max. at A (ii) KE max. at B. 2
(b) decelerating, KE is being converted to GPE. 2
7 (a) velocity–time graph. 4
(b) (i) acceleration = velocity change/time = (15 – 0)/15 = 1 m/s2. 3
(ii) deceleration = (0 – 15)/20 = (–) 0.75 m/s2. 2
(iii) distance = area under graph = (1/2 × 15 × 15) + (25 × 15) + (1/2 × 15 × 20) = 637.5 m; 4
(c) resultant force is zero so forces are balanced. 1
8 (a) energy efficiency = useful energy output/total energy input. 2
(b) (i) energy that would be wasted is used to provide useful heating. 2
(ii) power station must be near the buildings to be heated/slightly less electricityis produced. 1
9 (a) Molly will be thrown forwards (possibly through the windscreen) because the brakesact on the car, not on Molly so she carries on moving forward at her original speed; 3
(b) Molly would not be thrown forwards. The seat belt would have stretched slightlyand slowed Molly down gradually; so that there would be less force on her. 2
10 (a) At B, GPE + KE, at C elastic PE (+ some thermal energy), at D, GPE. 4
(b) (i) GPE = mgh; GPE at A = 0.05 × 10 × 1.0 = 0.5 J, GPE at D = 0.05 × 10 × 0.2 = 0.1 J 5
(ii) energy ‘lost’ = 0.5 – 0.1 = 0.4 J. 2
(iii) transferred to thermal energy (and sound) on impact; transferred to thermalenergy due to air resistance. 2
11 (a) (i) 1 N (ii) 3 N. 2
(b) same. 1
(c) Air resistance is a greater proportion of the weight of A than of B so the accelerationof A is reduced more than that of B, so A travels more slowly (and takes longer toreach the bottom). 3
12 (a) constant velocity. 1
(b) WD = force × distance moved = 500 × 25 = 12500 J. 3
(c) 12500 W. 1
(d) efficiency = useful power output/total power input = 12 500/50 000 = 0.25 (25%). 3
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(e) bigger force forwards than backwards/resultant force forwards. 1
(f) as speed increases, air resistance increases as well; eventually the air resistance forceis equal to 700 N so the acceleration is zero (balanced forces). 2
13 (a) 400 N. 1
(b) WD = force × distance moved = 400 × 15 = 6000 J. 3
(c) 6000 J. 1
(d) efficiency = useful power output/total power input = 6000/10 000 = 0.6 (60%). 3
(e) time. 1
14 (a) Air trapped in cavity is a bad conductor of heat so heat transfer from inside to outsideis greatly reduced. 3
(b) Mineral wool prevents large convection currents circulating in the cavity, this led toheat loss by convection in the 1950 house. 2
(c) Better sound insulation/cheaper fuel bills. 2
15 (a) Average speed = total distance/total time = 650/5 = 130 km/h(i) = 130/3.6 = 36.1 m/s (ii).This is an average speed because the train will accelerate/decelerate/stop on the way. 6
(b) F = MA, F = 300 000 × 0.5 = 150 000 N . 3
(c) a = F/m = 150 000/250 000 = 0.6 m/s2. 3
(d) Distance left = 400 km; time = 2 hours 48 min = 2.8 hours;average speed = 400/2.8 = 143 km/h. 4
16 (a) Thinking distance = speed × time = 220 × 0.7 = 14 m. 3
(b) Graph – constant speed of 20 m/s for 0.7 s then steady deceleration to stop after afurther 4 s. 4
(c) Deceleration = velocity change/time = 20/4 = 5 m/s2. 3
(d) Distance travelled = area under graph = (20 × 0.7) + (1/2 × 20 × 4) = 54 m; so yes. 4
(e) at 25 m/s the braking time would be 5 s. Stopping distance would be(25 × 0.7) + (1/2 × 25 × 5) = 80 m (so would hit child). 4
17 (a) (i) Acceleration = F/m = (90 000 – 30 000)/3000 = 20 m/s2. 4
(ii) Velocity after 3 s = acceleration × time = 20 × 3 = 60 m/s. 3
(b) Acceleration = –10 m/s2 (or deceleration of 10 m/s2). 1
18 (a) Thinking time = distance/speed = 6/10 or 9/15 = 0.6 s. 3
(b) speed thinking braking stopping KE (answer to g (i))m/s distance distance distance in J
in m in m in m10 6 6 12 30 00015 9 14 23 67 50020 12 24 36 120 00025 15 38 53 187 50030 18 55 73 270 00035 21 74 95 367 500 5
(c) Increases proportionally. 2
(d) Increase, the driver’s brain would take longer to react. 2
(e) Increase, friction force reduced. 2
(f) Assuming both sets of brakes are equally efficient, the minimum distance apartshould be the thinking distance of 18 m so allowing for variations in reactiontimes and brakes a little more than 18 m should be allowed. 3
(g) (i) See table above. 6
(ii) Graph. 4
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(iii) KE and braking distance are proportional since graph is a straight line throughthe origin. (2)
(iv) Braking force × distance = change in KE, so gradient of graph = braking force.
Calculation of gradient – large triangle, read accurately, correct calculation.
Braking force in N (approximately 5000 N). (6)
19 (a) Terminal velocity is the constant velocity reached by a falling object when its weightis equal to the upward resistive force. (2)
(b) With arms outstretched the person displaces more air molecules so the air resistanceforce is greater and (s)he reaches terminal velocity sooner so at a lower velocity. (3)
(c) (i) density is very low. (1)
(ii) Fewer molecules per unit volume means the air resistance force is smaller so ittakes longer to reach terminal velocity and its value is higher. (2)
(d) Friction with the air molecules when falling at a high speed produces lots of heat. (2)
(e) High melting point/good thermal insulator/flexible, soft. (2)
(f) The air is very thin/density low/fewer molecules per unit volume at such a highaltitude so the air pressure is so low that, even allowing for the increase on reachingthe speed of sound, it will not become too large. (2)
(g) As the air thickens (its density increases) the air resistance force will increase; sothat it becomes greater than his weight; this will make him decelerate. (3)
(h) Parachute opens – greater upward force so rapid deceleration; reaches a new, lowerterminal velocity; gradually comes to rest on hitting the ground (bends knees so hestops more slowly). (3)
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Wave properties
Introduction spread
In-text questions
(a) Vibrates it.
(b) Damage hearing/go deaf.
(c) Stars are luminous/produce their own light, moon reflects light from Sun.
(d) Rays drawn with ruler, passing through pinhole, inverted image.
(e) Straight lines from footballer through periscope to eye, good reflections on mirror.
Spread 3.1
In-text questions
(a) strings.
(b) skin.
(c) reed.
(d) transverse.
Thinking further questions
1 Water moves up and down,
wave moves outwards,
boat only moves up and down.
2 Moving weight up causes compression, takes time to move up reflect and return.
Spread 3.2
In-text questions
(a) 30 ÷ 60, = 0.5 Hz.
(b) metre.
(c) 5 mm, 16 mm
(d) 16 mm
(e) speed = distance ÷ time = 100 ÷ 20 = 5 m/s.
Thinking further questions
1 (a) increases/higher.
(b) decreases, to half.
2 speed = frequency × wavelength = 7 × 0.2 (or 7 × 20) = 1.4 m/s (or 140 cm/s).
3 (a) distance = speed × time = 300 × 0.75 = 225 m.
(b) speed of light very much larger/infinite.
Spread 3.3
In-text questions
(a) Angle of incidence equals angle of reflection.
(b) Originate from or converge to a point which is closer to barrier than centre of circlewhich forms the barrier, or words to that effect.
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Thinking further questions
1 (a) 30°
(b) Wavefronts drawn with ruler, incident with wavelength of 2 cm, reflected with samewavelength as incident, angle of incidence at 30°, angle of reflection same as angle ofincidence
2 6 wavefronts shown, 4 incident, 2 reflected, 8 cm accurate, 2 cm accurate, reflectedoriginate 8 cm behind barrier.
Spread 3.4
In-text-questions
(a) 65°.
(b) at focus.
(c) rays drawn with ruler, reflected rays appear to diverge from focus.
Thinking further questions
1 Wider field of view, or words to that effect.
2 Soft material, absorb sound/reduce reverberation.
3 (a) gets even wider.
(b) difficult to mark exact position of centre of ray.
Spread 3.5
In-text questions
(a) speed = frequency × wavelength, if speed is lower then wavelength decreases iffrequency stays same.
(b) equal.
Thinking further questions
1 Waves drawn with ruler, consistent wavelength, refraction at deeper water, longerwavelength in deeper water, consistent wavelength, angle of refraction greater thanangle of incidence.
2 (a) Points correctly plotted, smooth curve drawn, comments on curve, decreasing gradient/levels off, passing through origin.
(b) Sines correct to 2DP 0.17; 0.34; 0.50; 0.64; 0.77; 0.87; 0.940.12; 0.22; 0.33; 0.42; 0.52; 0.57; 0.63.
Straight line drawn with ruler, comments on straight line, passing through origin/proportional.
Spread 3.6
In-text questions
(a) On the film.
(b) Appears to raise left hand.
(c) To make sure the reading is taken at correct angle/line up image of needle behind needle.
(d) (360 ÷ angle between mirrors) – 1
(e) Infinite number, angle between mirrors is zero.
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Thinking further questions
1 Driver of car in front sees writing correct way round in rear view mirror or words to thateffect.
2 Below where he sees the fish.
3 Raises right hand.
Spread 3.7
In-text questions
(a) 0.5 m.
(b) 1 m.
(c) Radio 4 – 1500 m
Radio 5 – 330 m
(d) 3 × 10–6 m/0.000 003 m/3 m
(e) Door width comparable to wavelength of sound, much bigger than wavelength oflight, light does not diffract.
Thinking further questions
1 (a) Idea that long waves diffract most and short waves and microwaves diffract least,idea that no/little diffraction needed to receive at house D, idea that a lot of diffractionneeded to receive at house A.
(b) Taller/higher aerial.
2 (a) 1 cm diameter light spot, sharp edges.
(b) Light spot larger than pinhole diameter.
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Wave properties
Answers
1 (a) true
(b) false
(c) true
(d) false
(e) true. 5
2 (a) Air vibrates, longitudinal wave/compressions and rarefactions. 2
(b) Vibrates, at 600 Hz. 2
3 X – C, Y – A, Z – B. 3
4 D. 1
5 D. 1
6 450 m/s, 5 m/s, 4 m, 40 Hz, 1.67 Hz. 5
7 1.7 m tall, 3 m, behind mirror/virtual, on same normal, walking southerly, upright,waves left hand. 7
8 distance = speed × time, = 330 × 5, = 1650 m. 3
9 (a) Mirrors on both cushions, shine light from above white ball to RH mirror, adjustangle, until reflection from bottom mirror hits red. 4
(b) Balls behave like light, angle of incidence equals angle of reflection. 2
10 (a) Points plotted correctly, smooth curve. 2
(b) 72°. 1
(c) 8. 1
(d) 4. 1
(e) Graph gives value of 3.5 images, cannot have part of an image. 2
11 Curved shape with wave having travelled further towards AB. 1
12 (a) increases. 1
(b) unchanged. 1
(c) increases. 1
13 (a) Wavefronts continue to be straight showing no diffraction, consistent wavelengthbefore harbour entrance, same wavelength inside harbour. 3
(b) Wavefronts semicircular showing diffraction inside harbour, consistent wavelength. 2
(c) Wavelength from large yacht similar to harbour entrance gap, very short wavelengthfrom motorboat much less than harbour entrance gap, diffraction only if similardistances. 3
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Using waves
Introduction spread
In-text questions
(a) red, orange, yellow, green, blue, indigo, violetright order.
(b) red and blue magentablue and green cyangreen and red yellowred and blue and green white.
(c) red tomato + red light redblue car + green light blackyellow daffodil + red light redwhite paper + yellow light yellow.
Spread 4.1
In-text questions
(a) frequency = velocity/wavelength = 300 000 000/1500 = 200 000 Hz (200 kHz).
(b) wavelength = velocity/frequency = 300 000 000/1018 = 3 × 10–10 m.
(c) violet.
Thinking further questions
1 Gamma rays have shorter wavelength than X-rays, X-rays have shorter wavelengththan visible light, the shorter the wavelength the more energetic, the more energeticthe more penetrating.
2 gamma 1019 Hz – 1023 HzX-rays 1017 Hz – 1019 Hzultraviolet 1015 Hz – 1017 Hzinfrared 1011 Hz – 1015 Hzradio 103 Hz – 1012 Hz.(answers to within an order of magnitude).
Spread 4.2
In-text questions
(a) Blue flames emit light with a shorter wavelength, shorter wavelengths have moreenergy.
(b) Foil reflects radiation back to the potato.
(c) 20 × 15, = 300 minutes (5 hours).
Thinking further questions
1 Reduce amount of ultraviolet radiation to the eyes.
2 Working underground/little sunlight, therefore little exposure to ultraviolet radiation,ultraviolet radiation helps in the production of vitamin D.
3 Car engine hot, tyres hot, people in car.
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Spread 4.3
In-text questions
(a) Microwaves can penetrate flesh, transfer energy to water in human body.
(b) Very short wavelength, almost no diffraction.
(c) Short wavelength, little diffraction.
(d) uhf has to be almost in line of sight since little diffraction/uhf is ground basedtransmission and reception, satellite dishes have to be in line of sight/satelliteis in line of sight since no obstructions such as hills or tall buildings.
(e) Frequent exposure to X-radiation is damaging to the human body.
(f) Lead vest, absorb X-rays, reduce exposure/damage to patient.
(g) 100 000 000 m/s.
Thinking further questions
1 time = distance/speed = 90 000/300 000 = 0.3 s.
2 long waves are reflected from the ionosphere, greater diffraction.
3 (a) distance = speed × time = 3 × 108 × 6 × 10–7 = 180 m.
(b) 90 m.
(c) No need to adjust, distance between cars greater than stopping distance.
4 X-rays or gamma rays have wavelengths of similar order of size to atomic distances,therefore diffraction takes place.
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In-text questions
(a) Different colours have different wavelengths, therefore refract at different angles.
(b) Entering along the normal/right angle to surface.
(c) 45°, greater than critical angle.
(d) Current produces heating effect, energy lost, very little light loss in optical fibre,little energy lost.
Thinking further questions
1 No interference in signal.
2 Does not matter how the light passes, important to see image in the same patternas the object.
Spread 4.5
In-text questions
(a) Stronger reflected signal, received sooner.
(b) Distance = speed × time = 1500 × 0.4 = 600 there and back, depth = 300 m.
(c) Looking for fish/submarines.
(d) To collect low sound levels.
(e) Emits signal, reflected off opposite wall, time taken for reflection halved,distance = speed × time.
Thinking further questions
1 (a) wavelength = velocity/frequency = 1500/150 000, 0.01 m
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(b) boat slower than dolphin.
(c) distance = speed × time = 1500 × 0.05 = 75 there and back, fish distance = 37.5 m.
2 Audible frequency means relatively long wavelength, sound diffracts around fish,ultrasound is reflected.
Spread 4.6
In-text questions
(a) Produced by vibration, P waves are longitudinal, travel through dense objects.
Thinking further questions
1 Most densely populated cities are in earthquake zones.
2 (a) seismometer S left to right P wave, S wave, L wave.
(b) T is in shadow of core, no S wave detected.
Spread 4.7
In-text questions
(a) S waves do not travel through liquids so shadow confirms outer liquid core,reverberations indicate that not all core is liquid therefore a solid inner core.
(b) Rock type.
(c) Less dense than surroundings.
(d) Crust.
(e) 12/12 800 = 0.000 9375 (0.093 75%).
Thinking further questions
1 (a) Similar coastal outlines, fossil evidence from cynognathus, mesosaurus, glossopteris.
(b) Fossil evidence from lystrosaurus, glossopteris.
2 Average density of core and mantle greater than 5.5 g/cm3.
Spread 4.8
In-text questions
(a) Plate boundaries correspond to major earthquake zones.
Thinking further questions
1 (a) Friction.
(b) Forms part of the mantle.
2 speed = distance/time = 7000 000/200 000 000 = 0.035 m/year (3.5 cm/year).
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Using waves
Answers
1 (a) false 1
(b) true 1
(c) false 1
(d) false 1
(e) true. 1
2 (a) ultraviolet 1
(b) X-rays 1
(c) gamma 1
(d) radio 1
(e) gamma 1
(f) infrared 1
(g) microwaves 1
(h) visible light. 1
3 (a) yes 1
(b) green roof, low energy loss. 2
4 reflected, refracted, diffracted, travel at speed of light, transverse waves. 5
5 (a) crust 1
(b) mantle 1
(c) magma. 1
6 All signals pick up noise, analogue noise cannot be distinguished from signal, duringtransmission noise is amplified, digital noise can be removed/clear signal. 4
7 (a) Refraction on entering catseye, total internal reflection at first rear boundary, totalinternal reflection at second rear boundary, refraction on leaving catseye. 4
(b) Helps to focus light. 1
8 For P wave distance = speed × time = 10t, for S wave distance = speed × time = 6 (t + 600),10t = 6 (t + 600) 4t = 3600, t = 900s, d = 9000 km. 5
9 (a) Magma from Earth’s interior oozes along mid-oceanic ridges, creates new floor,spreads away from ridge crest. 4
(b) Rocks on sea-floor only 180 million years old, other rock fossils much older. 2
(c) Sea floor older further from ridge crest, oceanic crust sinking into trenches. 2
(d) Rises. 1
(e) Mid-Atlantic ridge. 1
(f) S. America, Africa, India, Australasia, Antarctica. 5
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Radioactivity
Introduction spread
In-text questions
(a) electron: mass = 0, charge = –1neutron: mass = 1, charge = 0proton: mass = 1, charge = +1.
(b) nucleus.
(c) proton, neutron.
(d) Isotope: same number of protons, different number of neutrons.Atomic number: number of protons in nucleus.Mass number: number of protons + neutrons/number of nucleons in nucleus.
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In-text questions
(a) 1.
(b) 3.
(c) protons = 88, neutrons = 138.
(d) 91231
89227
24Pa Ac He→ + .
92238
90234
24U Th He→ + .
93237
91233
24Np Pa He→ + .
(e) +, 2.
(f) 1740
1840
10Cl Ar e→ +− .
2966
3066
10Cu Zn e→ +− .
93238
94238
10Np Pu e→ +− .
Thinking further questions
1 (a) Gases in the air.
(b) (¾), 75%.
2 Evidence of working either by individual decay or total mass number and atomic numberchange, 82
208Pb.
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In-text questions
(a) 100.
(b) 270 000 000 m/s.
(c) Reduces to 1/16th.
Thinking further questions
1 Beta radiation, small reduction in count rate.
2 Alpha radiation – most absorbed by aluminium foil.Beta radiation – some passed through foil, none through lead.
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In-text questions
(a) approximately 167.
(b) 625.
(c) 15 hours.
(d) 50 hours.
(e) 65 hours.
Thinking further questions
1 Activity = number of nuclei which decay ÷ time taken in seconds,= 36 600 ÷ (10 × 60) = 61 Bq.
2 Correctly plotted points, smooth curve, 37.3 minutes.
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In-text questions
(a) Gamma radiation too penetrating, not enough change in radiation detected.
(b) Beta radiation absorbed by aluminium or steel cans, gamma radiation will pass through.
(c) Relatively constant decay rate to calibrate instrument.
(d) Does not penetrate as far into the body, causes less damage to patient.
Thinking further questions
1 No reading from X to Y, sudden increase at Y, no reading beyond Y.
2 Source of gamma radiation used, constant reading from X to Y, no reading beyond Y.
3 Attack cancer from many directions, each beam does less damage to body on way to cancer.
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In-text questions
(a) Plastic would melt/bend in boiling water.
(b) Animals eat plants.
(c) Moon formed later than Earth.
Thinking further questions
1 They are being applied to the human body so any bacteria in cosmetics could be harmful.
2 Over the large timescale involved, the uranium effectively decays to lead with little timetaken in the other decays, enabling comparisons to be made directly between the amountsof uranium and lead present in a rock sample.
3 There may have been quantities of other elements present which have decayed or the finalelement in the decay chain may have been present, or the relative compositions may havebeen different in the past.
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In-text questions
(a) Cancer treatment involves high doses of radiation, damages cells, affects bodyprocesses.
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(b) Few millimetres of aluminium.
Thinking further questions
1 Body still developing, exposure to radiation could damage body too much.
2 Reduces it to about 1/100th.
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Radioactivity
Answers
1 Protons, neutrons (either order), nucleus, electrons, nucleus, positive, negative. 7
2 Electromagnetic radiation, not particle. 2
3 More ionising, shorter range. 2
4 A – false, B – true, C – true. 3
5 Both have 92 protons, 235 has 143 neutrons, 238 has 146 neutrons. 3
6 Count due to radon = 1600 counts per minute, five half-lives reduces to50 counts per minute, 5 × 56 = 280 seconds. 3
7 Alpha radiation short ranged, will not reach body, gamma radiation long range andpenetrates body. 3
Alpha radiation absorbed by tissue in body causing damage, gamma radiationpenetrating and leaves body. 2
8 Half-life too short. 1
9 (a) Radiation is emitted randomly. 1
(b) Average count rate 1086 – 32 = 1054 cpm, constant during the day so half-life muchlonger than 24 hours. 3
10 (a) Radioactivity from Chernobyl scattered over very large area. 1
(b) Splitting of the atom into smaller atoms. 1
(c) When all the uranium has been used up. 1
(d) Boron. 1
(e) Acute radiation sickness, death. 2
(f) Metres of concrete. 1
(g) Contains more uranium-235 than normal, uranium-235 is fissionable. 2
(h) More than that is beyond the critical limit, nuclear explosion. 2
(i) Iodine, caesium. 2
(j) Thyroid cancer, from iodine. 2
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The Earth and Universe
Introduction spread
In-text questions
(a) Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.
(b) Moon.
(c) Gravity.
(d) Sources – Star, Sun,Reflect – Earth, Mars, Moon.
(e) Communication, space research, weather, mapping/surveying, navigation, spying.
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In-text questions
(a) Venus.
(b) Jupiter, Saturn.
(c) Smaller, further away.
(d) Mars and Jupiter.
(e) Planet – circular, comet – elliptical.
(f) Stays in same place above Earth.
(g) Orbits above the North and South poles.
(h) Distance to Mercury ¼ distance to Mars, inverse square, 42 = 16.
(i) X at closest distance to the Sun.
Thinking further questions
1 Points correctly plotted, best line, answer from student’s graph.
2 Radius of orbit = radius of Earth + height above Earth = 6400 + 36 000 = 42 400,circumference = 2r, speed = distance ÷ time, = 3 km/s.
3 (a) Mercury 4.07, Venus 3.03, Earth 2.56, Mars 2.07, Jupiter 1.13, Saturn 0.83, Uranus 0.59,Neptune 0.47, Pluto 0.41.
(b)1
speed= 0.06, 0.11, 0.15, 0.23, 0.79, 0.44, 2.83, 4.54, 5.96, points correctly plotted, straight line
graph, passing through origin.
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In-text questions
(a) Same number of protons, different number of neutrons in nucleus.
(b) 600 000 000 tonnes per second 600 × 106 × 60 × 60 × 24 × 365 × 10 × 109 tonnestotal = 1.9 × 1026 tonnes so statement true.
(c) Formed from material from exploding supernova so had previously been a star.
(d) Light cannot escape so no reflection.
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Thinking further questions
1
2 m = E/c2 = 400 × 1024/(300 × 106)2, = 4.4 × 109 kg.
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In-text questions
(a) Milky Way.
(b) Blue.
(c) Blue shift.
(d) Moving towards us.
(e) Darker, colder.
Thinking further questions
1 Quasars are 12 billion light years away, may be things beyond.
2 Able to support life, water, right atmosphere, temperature, form enclosed/artificialenvironment.
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neutron star
protostar
red giant
white dwarfblue supergiant
red supergiant
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The Earth and Universe
Answers
1 A – false, B – false, C – true, D – false, E – true, F – false, G – false, H – true. 8
2 Side moving towards us moving faster than whole galaxy moving away, blue shift. 2
3 A – blue giant, B – red giant, C – white dwarf. 3
4 (a) orbit radius = Earth radius + height = 6400 + 350 = 6750 km, circumference = 2r = 2 ×6750, = 42411.5 km. 3
(b) time = distance ÷ speed, = 42411.5 ÷ 7.85 = 5403 s, = 90 minutes. 3
5 (a) Meteorite. 1
(b) 3.5 billion years. 1
(c) 16 million years ago. 1
(d) 16 000 years ago. 1
(e) Buried in ice in Antarctica. 1
(f) 1984. 1
(g) When Earth and Mars are in correct positions for a space mission. 1
(h) Samples of magnetite could be produced by bacteria; because of shape chemistry andenvironment; on Earth water and chemicals means life, why not elsewhere? Individualevidence not conclusive; evidence taken as whole could be more so, much work stillneeds to be done. 5
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Using electricity
Introduction spread
In-text questions
(a) Any 5 appliances used in the home e.g. kettle, TV, fire, microwaveoven, CD player.
(b) Any 5 appliances used outside the home, e.g. portable radio, portablecassette or CD player, torch, car starter motor, mobile phone, electrictrain.
(c) An electric current can pass through an electrical conductor but notthrough an insulator. Conductors – any metal, such as copper, iron.Insulators – wood, plastic (for example).
(d) An electric current is a flow of electric charge in a conductor. Unit –ampere (A).
(e) Voltage is the energy possessed by the charged particles. Unit – volt.(f) Charge carriers collide with the atoms in the conducting medium.
Unit – ohm.(g) V = IR I = V/R R = V/I.(h) R = V/I = 230/10 = 23 ohms.(i) Thermal energy.(j) A large current is needed to produce heat.
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In-text questions
(a) Electrons are removed from the perspex ruler due to friction whenrubbed with the duster. This leaves the perspex ruler with fewerelectrons than normal, so it is positively charged.
(b) Hair becomes charged due to friction with the comb. All the hairs getthe same charge. Like charges repel so the hairs move apart.
(c) If the comb is positively charged it attracts electrons in the paper.These electrons move towards the top surface of the paper making itnegatively charged. Opposite charges attract so the tiny pieces ofpaper move towards the comb, (reverse argument for a negativelycharged comb).
Thinking further questions
1 Friction transfers electrons from one part of the film and deposits them onanother part, so parts of the film are positively charged and partsnegatively charged. Opposite charges attract so the film sticks to itself.
2 The balls have the same charge in equal amounts. 3 (a) Electrons move from the comb onto Jaina’s hair. Jaina’s hair gains
electrons so is negatively charged; the comb loses electrons andbecomes positively charged.
(b) Jaina’s hairs all become negatively charged so move apart as likecharges repel.
4 (a) The ruler becomes charged (positively) by friction when rubbed onAlex’s sleeve.The ruler therefore attracts electrons in the watertowards it and the water bends towards the ruler.
(b) Polythene becomes negatively charged. Electrons in the water arerepelled away leaving the water near the rod positively charged.
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Opposite charges attract so the water bends towards the ruler asbefore.
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In-text questions
(a) Yes. The dust particles would be given a positive charge by the wiresand be attracted to the negatively charged plates.
(b) All the paint particles have the same charge. Like charges repel so thepaint spreads out.This gives an even coating over a wide area on thearticle being painted.
(c) The screen becomes charged as the electrons strike it. The chargedscreen attracts small dust particles to it as they become charged byinduction.
(d) The inert gas avoids the risk of fire as no oxygen is present and the gasis unreactive.
Thinking further questions
1 Plastic is an insulator so charge can build up on it and may cause a spark,igniting the fuel. Metal is a conductor so any charge is conducted away.
2 The car becomes charged by friction with the air as it moves along theroad. The rubber tyres insulate it from the ground so charge builds up.When you touch the metal car door (a conductor) charge passes throughyou giving you an electric shock.
3 A tree is likely to be the tallest object around so is most likely to be struckby lightning. If you are standing under the tree you will be electrocutedalso.
4 This prevents charge building up on the aircraft. This could cause a sparkthat might ignite the fuel. (See answer to Q 2).
5 The powder becomes charged by contact with the wire and sticks to thefingerprint but not to the clean paper.
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In-text questions
(a) The ball would oscillate more quickly. (The ammeter would indicatea larger current.)
(b) Q = It Q = 2A × 60 s = 120 C.(c) 1C = 1/(1.6 × 10–19) = 6.25 × 1018 electrons.(d) 12 J.
Thinking further questions
1 Circuit showing battery and motor in series with current direction from +to – of battery. Arrows for electrons in opposite direction.
2 More electrons flowing per second, increased speed of electrons. 3 (a) Q = It = 2A × 30 s = 60 C.
(b) Energy, E = VIt = 12 × 2 × 30 = 720 J or 12 V = 12 J/C so energy = 12 ×60 = 720 J.
(c) Light energy produced = 0.1 × 720 = 72 J. 4 (a) So that charges can move over the surface of the ball.
(b) The ball completes the circuit, carrying charge from one plate to theother. An ammeter connected between one of the plates and the vande Graaff would indicate a current.
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In-text questions
(a) P = VI I = P/V = 1150/230 = 5 A.(b) To stop the current reaching the appliance.(c) So that they all get the full voltage, no matter how many lights are
switched on or appliances in use. So that the lights and appliances canall be switched independently and if a fault occurs in one theremainder still work.
Thinking further questions
1 toaster power = 230 × 3.5 = 805 W.kettle current = 2645/230 = 11.5 Acomputer power = 230 × 0.4 = 92 W.
2 (a) Cookers require a larger current than the maximum 13 A allowed in aring-main.
(b) Power = VI = 230 × 30 = 6900 W. 3 Ease of adding/removing sockets with minimum of wire.
All appliances in parallel so get the full voltage no matter how many areswitched on (as long as the maximum current of 30 A is not exceeded).Current to each socket flows by two paths so increasing thecapacity/allowing thinner wire to be used.
4 Current in 1 lamp = 60 W/230 V = 0.26 ANo. of lamps = 5/0.26 = 19.
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In-text questions
(a) A short circuit effectively removes part of the circuit, reducing theresistance. This increases the current and more heat is produced; thismay cause a fire.
(b) P = VI I = P/V = 920/230 = 4 A 5 A fuse required.(c) If the fault resulted in a bare wire touching the case, it would become
charged. If someone touched the case, charge would flow throughthem, giving them an electric shock.
Thinking further questions
1 Water conducts electricity so you could get an electric shock.
There should be no conventional light switches or power sockets in bathrooms.Lights are switched via an insulating pull cord so the hands are well away fromthe electrical connections. The only power socket permitted is a special shaverpoint.
2 TV 0.5 A 3 A fusefan heater 5.0 A 13 A fusevideo recorder 0.2 A 3 A fusewashing machine 12.0 A 13 A fuse
3 High-powered appliances are designed to produce heat. 4 As the current increases the bimetallic strip gets hotter. Brass expands
more than iron so it bends upwards, past the brass rod, breaking thecircuit. As it cools down it straightens and the circuit breaker can be resetonce the fault has been rectified. (If the bimetallic strip bent the other wayit would reconnect the circuit as it cooled down, like a thermostat.)
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In-text questions
(a) Energy = power × time = 60 W × (2 × 60 × 60)s = 432 000J (432 kJ).(b) Energy = VIt = 230 × 10 × (6×60) = 828 000 J (828 kJ).(c) Lamp – energy transferred = 0.060 kW × 2 h = 0.12 kWh.
Kettle – energy transferred = 2.3 kW × (6/60) h = 0.23 kWh [P = VI =230 × 10 = 2300 W = 2.3 kW].
(d) 1 kWh = 1000 W × 3600 s = 3.6 × 106 J.(e) Cost = 1500 × 10p = £150.(f) No. of kWh = 1 × 4 = 4 (kWh).
Cost = 4 × 7p = 28p.
Thinking further questions
1 appliance energy (kWh) cost Q2 • energy (J)drill 0.45 4.5p 1.62 × 106
shower 16 £1.60 5.76 × 107
fire 40 £4.00 1.44 × 108
vacuum cleaner 0.75 7.5p 2.7 × 106
CD player 1.2 12p 4.32 × 106
3 No. kWh = 0.1 × 7 = 0.7 (kWh).Cost = 0.7 × 8p = 5.6p.
4 Total power = 3.05 kW. No. of kWh used in 5 hours = 15.25.Cost = 15.25 × 8p = £1.22.
5 Compile a table similar to that in Q1 for any choice of 5 appliances.Add up the individual costs per week.(Remember this is an estimate so the final answer should be rounded off to1 or 2 s.f.)
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Using electricity
Answers
1 electrons, duster, rod, negatively, positively, electrons, insulators, attracts, negatively,opposite, attract. 11
2 (a) Dilip became charged by friction with the carpet, the metal door handle conductselectricity so current passed through him (giving him an electric shock). 3
(b) Electrons were rubbed off the set square due to friction leaving the set square withless electrons than normal (so positively charged). 3
3 (a) 18022 – 17313 = 709 kWh. 1
(b) 709 × 8p = £56.72. 2
4 (a) (i) Green and yellow/earth wire connected to case of microwave oven. 1
(ii) If the case becomes charged due to a fault, the charge flows down the earthwire to the ground/causes a large current in live and earth wires so melts fuse,and user does not get an electric shock. 2
(b) 500 J of energy every second is transferred into other forms. 2
(c) (i) The fuse melts if the current exceeds 3 A, protecting the appliance. 2
(ii) P = VI; I = P/V = 500/230; = 2.17 A so 3 A fuse is correct. 3
5 vacuum cleaner 750 Welectric blanket 250 Wlamp 60 Wkettle 3000 Welectric fire 1000 WCD player 120 W. 6
6 (a) heaters: 4.5 kW × 4 h = 18 kWh
lamps: 0.55 kW × 6 h = 3.3 kWh
total = 21.3 kW. 3
(b) No. of kWh in 90 days = 21.3 × 90 = 1917 kWh.
Cost = 1917 × 8p = £153.36. 2
7 (a) (i) 3000 J (ii) 3000 J × (2 × 60 × 60)s = 2.16 × 107 J. 3
(b) No. of kWh = 3 × 2 = 6 (kWh). 1
(c) 1 kWh = 2.16 × 107 J/6 = 3.6 × 106 J. 2
8 (a) (i) By friction. 1
(ii) Paint spreads out as like charges repel 2
(iii) Covers large area evenly. 1
(b) To attract the paint so that it sticks well. 2
9 (a) Fuse does not melt until current reaches 13 A; Charlie would get an electric shockat a much smaller current. 2
(b) Protects the lawn mower/stops it catching fire if a fault occurs. 1
(c) (i) 30 mA is much greater than the maximum safe current so it would not be verysafe if this current passed through Charlie. 2
(ii) 30 – 1 = 29 mA. 1
(iii) Resistance of lawn mower is much less than the resistance of Charlie. 1
(d) Rubber soled footwear so that Charlie is insulated from the ground and chargecannot flow to the ground through him. 2
10 (a) Batteries. 2
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(b) Milkfloats are noted for being slow and having a short range. 2
(c) (i) Anything sensible – e.g. perimeter of island is about 30 miles so visitor coulddo this trip 4 times in 4 days. 2
(ii) Batteries can be recharged easily/overnight. 1
(d) d.c. 1
(e) Quiet; no pollution from fumes. 2
(f) Recharging takes 7 hours/limited range (125 miles); so quiet there is a risk topedestrians/horns used as warning adding to noise pollution. 2
Physics TB7 Answers: end of teaching block
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Electromagnetism
Introduction spread
Intext questions
(a) A magnetic material is capable of being magnetised, e.g. iron, steel,nickel, cobalt. Attract in (i); repel in (ii).
(b) A hard magnetic material is difficult to magnetise but retains itsmagnetism, e.g. steel. A soft magnetic material is easy to magnetisebut loses its magnetism as soon as the magnetising force is removed,e.g. iron.
(c) A magnetic field is an area around a magnet where its effect is felt.(d) Magnetic induction is when a magnetic material is magnetised by
being placed near to, or in contact with, a magnet. Demonstrate bypicking up a line of pins with a magnet.
(e) (i) Straight wire – circular magnetic field lines in clockwisedirection.
(ii) Solenoid – magnetic field similar to that of a bar magnet with Spole on LHS.
(f) Pattern remains the same but the direction of the magnetic field isreversed.
(g) S pole on LHS, N pole on RHS.(h) (i) iron rod becomes magnetised (ii) loses its magnetism.
Steel would stay magnetised when the current was switched off.(i) Electric bell, motor, relay, separating ferrous/non ferrous materials,
moving cars/ferrous scrap around, removing tiny pieces of iron orsteel from the eye.The core is made from iron so that it loses its magnetism when thecurrent is switched off.
Spread 8.1
In-text questions
(a) Because the wire is flung out of the magnetic field like a stone from acatapult.
(b) The direction of the force would be unchanged.(c) Check that Fleming’s left-hand rule can be applied correctly.(d) A larger current will produce a louder sound.
Thinking further questions
1 Arrow upwards.(i) Stronger magnet/bigger current.(ii) Reverse the current direction/swap over the magnetic poles.
2 (a) Bigger force on the wire.(b) Smaller force on the wire.(c) Wire would oscillate as the direction of the force would change at the
same frequency as the applied a.c.
3 Force on wire less (sin x dependence).
4 Frequency of a.c. current in coil increases, but size of current is unchanged.
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In-text questions
(a) Use Fleming’s left-hand rule to check that the forces on the coil are asindicated.
(b) Because the direction of the forces on the coil reverse as it passes thevertical, so it would then rotate in the other direction.
(c) The iron core becomes magnetised and increases the magnetic field.This gives a bigger force on the coil/makes the motor more powerful.
Thinking further questions
1 E.g. Washing machine, electric sewing machine, dishwasher, foodprocessor, hair dryer, tumble dryer (any two).
2 (a) The motor would rotate in the opposite direction.(b) The motor would be more powerful/rotate faster.
3 Yes. An electromagnet, if connected to a d.c. supply, produces a magnetwith poles dependent on the current direction in the coil of theelectromagnet.
4 Several coils – each will have the maximum force on it at different timesso the average force due to all the coils will be approximately constant.Radial magnetic field – the sides of the coil are always perpendicular to themagnetic field as the coil rotates so the force on the coil is constant.
Spread 8.3
In-text questions
(a) The direction of the force on the electrons is reversed.(b) (i) The deflection of the meter (i.e. induced current) would reverse
(i.e. to left).(ii) The deflection would be as in (b) (i) (i.e. to left).(iii) An alternating current would be induced.
(c) If the current flows in a clockwise direction when looking at the endof the coil that end is a S pole, if the direction is anticlockwise, a Npole. (Or alternative rule if preferred.)
Thinking further questions
1 (a) The direction of the induced current reverses.(b) The induced current is smaller.(c) No induced current (no magnetic field lines are being cut by the wire).
2 Increases as magnet approaches coil, drops to zero when magnet is insidecoil, increases in the opposite direction as magnet leaves coil with slightlybigger magnitude since the magnet is moving faster.
3 Induced current increases as the car enters the tunnel, falls to zero whencompletely inside it, has a maximum value in the opposite direction as thecar starts to leave the tunnel, gradually reducing to zero when it is wellaway from the tunnel.If speed is doubled the magnitude of the induced current is doubled (andthe time scale is halved, but this is not shown on a graph of inducedcurrent against position).
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In-text questions
(a) Check correct use of Fleming’s right-hand rule.(b) More powerful magnets/more turns on the coil/wind coil on iron core.
(Any two.)(c) The change of current is in opposite directions (increasing/decreasing
currents).(d) Current reaches a constant value.(e) The current is constantly changing in magnitude and direction.
Thinking further questions
1 The faster he pedals the greater the induced voltage and the greater itsfrequency.
2 Double the output. 3 (a) Same frequency, greater magnitude.
(b) Half the frequency, smaller magnitude. 4 When giving current forces act on the sides of the coil which oppose the
motion and tend to slow down the rotation of the coil.
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In-text questions
(a)V
V
N
Np
S
p
S
=23010
9200=
NS
NS = 400.
(b) VPIP = VSIS 230 × IP = 10 × 5 IP = 0.22 A.(c) Heat loss = I2R so for a given current R must be reduced.This can be
done by using a wire of a material having a low resistance and/orusing a thicker wire.
(d) A laminated core increases the resistance of the core so eddy currentsare reduced. If R increases, I decreases for a given V.
Thinking further questions
1 It is a step-down transformer with a turns ratio (Np/NS) of 230/12. 2 A transformer needs a changing magnetic field so that a voltage is induced
in the secondary coil. Only an a.c. supply will provide a changing magneticfield in the core.
3 80 10 V 12 000. 4 (a) Np:NS = 230:9
(b) Power = V × I = 9 × 2 = 18 W(c) 18 = 230 × IP IP = 0.078 A.
Assumption – transformer is 100% efficient.
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In-text questions
(a) To provide a direct current; essential for the electromagnet.(b) A lot of water is needed for cooling.(c) Ice caps will melt causing flooding.
Climate changes affecting economies and lifestyles of variouscountries.
(d) Visual pollution as they are usually in areas of natural beauty.Artificial lakes flood land so that houses and farms may be lost andthey also alter the habitat of plants and animals.
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Thinking further questions
1 So that it reaches a higher temperature and provides more KE to turn theturbines.
2 E.g. Tidal barrier – flooding of land adjacent to the river estuary andchanges to habitat for wildlife. Wind turbines – take up a lot of room, arethought by many to be unsightly and make a lot of noise.
3 Wind farms take up a lot of space and there is not much spare land in thiscountry, but land is more widely available in developing countries.Suitable sites need to have a lot of wind, for instance, in coastal regions oron high ground. The specific country would need to be considered tocompare this.Visual and noise pollution is a problem in this country but is less likely tobother people in a developing country where other energy sources may notbe available and the land may not be as densely populated.(This is an open-ended question which lends itself to research anddiscussion.)
4 Points to be considered include:Will our energy requirements increase, decrease, stay the same?The need to develop alternative energy sources as fossil fuel suppliesrun out.Pollution associated with the burning of fossil fuels.Suitable alternative sources for this country – HEP, wind, tidal, wave – andlocations.Pollution associated with alternative sources.The pros and cons of nuclear power.Measures to save energy.
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In-text questions
(a) (i) P = VI I = P/V = 25 × 106/25 × 103 = 1000 APower wasted = I2R = (1 × 103)2 × 10 = 1 × 107 W.
(ii) I = 25 × 106/25 × 104 = 100 APower wasted = (100)2 × 10 = 1 × 105 W.
Thinking further questions
1 (a) To keep warm.(b) Both feet are at the same voltage so no current flows from one foot to
the other through the bird. 2 High voltage is necessary so that the current is kept as low as possible
(P = VI so large V means small I).This minimises heat losses in the powerlines; heat lost = I2R so it is important that I is small.
3 We need to increase and decrease the voltage before and after powertransmission (see answer to Q2). Transformers are used to do this and theyonly work with an alternating current, (d.c. voltages can be changed, but itis difficult to do so).
4 Power loss reduced by a factor of 10. But low resistance wires would be verythick so would need more support as they would be heavier. They wouldalso be more costly to produce as they would use a greater quantity of metal.
5 (a) Current much less at 230 000 V (1 A instead of 1000 A) so much lessenergy wasted as heat. Power loss = I2R. This is dependent on I2 so itis very important to keep the current as low as possible.
(b) Step down transformer with turns ratio of 1000:1 or by reducing thevoltage in stages.
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Electromagnetism
Answers
1 (a) commutator (b) rotates (c) magnetic field (d) transformer (e) brushes(f) alternating voltage. 6
2 (a) current direction correct (from left to right between poles). 1
(b) Magnetic field – shape; direction from N to S. 2
(c) Up. 1
3 A transformer is used to step up the voltage for transmission around the country. Thisreduces the current (I = P/V) keeping energy losses (= I2R) to a minimum. 3
4 (a) 1.5 (A), –2.6 (A), –1.5 (A). 3
(b) Graph – axes (quantity and unit), scales, plots, curve. 4
(c) a.c. as it has + and – values. 2
(d) (i) Larger current values, same frequency. 2
(ii) Larger current values, twice the frequency. 2
5 (a) (i) To the left. 1
(ii) The coil carrying a current is in a magnetic field,so there is a force on it given by Fleming’s left-hand rule. 2
(b) (i) Vibrates. 1
(ii) a.c. keeps changing direction. As the current direction changes the directionof the force on the coil changes. 2
(c) (i) The paper cone vibrates through a bigger amplitude.
(ii) The sound is louder. 2
6 (a) I = P/V = (25 × 106)/(400 × 103) = 62.5A. 3
(b) High voltage means low current so energy losses are kept as small as possible
P = VI and heat loss = I2R. 3
(c) Voltages need to be stepped up and down using transformers which only work on a.c. 2
7 (a) Clockwise, FLHR shows that there is a force up on the side PQ and down on RSforming a couple which turns the coil clockwise. 4
(b) Commutator reverses the direction of the current in the coil each time the coilpasses the vertical so that the forces on the coil are always in the same directionto keep it rotating. 3
(c) Bigger current/voltage, more turns on the coil, more powerful magnets, wind coilon iron core (any three). 3
(d) More sets of coils, bigger current/voltage, more powerful magnets (possiblyelectromagnets), radial magnetic field, more turns on the coil, use of iron core(any three). 3
(e) (i) Needle moves back and forth indicating an alternating current. 2
(ii) + and – in shape of a cosine wave (starting at a maximum); one complete cycle. 3
(iii) When PQ moves up through the magnetic field a current is induced in onedirection and when it moves down the current is in the opposite direction;there is no induced current when the coil is vertical as it is not cutting themagnetic field lines; it has its maximum value when the coil is horizontal/whenthe magnetic field, sides of the coil and direction of movement are all mutuallyperpendicular. 3
8 (a) Convection. 1
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(b) Wind turbines – wind turns the turbines to make electricity.
Fan – uses electricity to turn the blades of the fan making a wind. 2
(c) Greater wind speed gives the turbine more KE so generator gets more KE toproduce electricity. 2
(d) Need lots of wind so near the coast and on high ground. 2
(e) New lightweight materials used in the wind turbines, better electrical generatingproducts. 2
(f) Wind strikes the blades of the wind turbine giving them KE. This KE is used toturn the turbine connected to a generator which rotates magnets around a fixedcoil inducing a voltage in the coil. 4
(g) KE = 1/2mv2; if v doubles, the KE increases by a factor of 4 since v is squared;the mass of air striking the blades of the wind turbine every second also doublesso the KE is 8 times larger. 4
(h) Supplies of fossil fuels are running out; we are using more and more electricity. 2
(i) Nuclear/HEP/wind/wave/tidal/solar/biomass/geothermal (any three). 3
(j) Does not produce acid rain/contribute to the greenhouse effect/renewable/doesnot use fossil fuels which are in short supply/wind is free (any two). 2
(k) Wind does not always blow/noisy/need a large number to produce a reasonableamount of electricity/occupy a large area/visual pollution/few ideal sites/usuallyin areas of natural beauty (any two). 2
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Electronics and control
Introduction spread
In-text questions
(a) R =230/0.5 = 460 Ω.(b) (i) V = 125 V (ii) 15 C.(c) (i) V = 8 V (ii) 4 V (iii) 2 Ω.(d) (i) Resistor whose resistance changes with the light intensity falling
on it.(ii) Resistor whose resistance changes with temperature.
(e) (i) Lamp will go out.(ii) The ammeter reading increases because closing the switch
short-circuits the lamp, reducing the effective resistance in thecircuit.
(f) (i) 3A (ii) 13 A.(g) Iron is easily magnetised but loses its magnetism as soon as the
current is switched off.
Spread 1.1
In-text questions
(a) (Check the truth table is correct).(b) (Check the truth table is correct).(c) OR gate.
Thinking further questions
1 ball cube outcome
red red lose
red blue lose
blue red lose
blue blue win
AND logic.
2 NOT
3 AND
4 NOT; add an AND gate with the other input connected to a moisture sensor.
Spread 1.2
In-text questions
(a) Temperature and moisture sensors.(b) OR.(c) Current in coil magnetises the two parts of the reed so that they
attract each other, completing the circuit.(d) To keep the current low so that the LED is not damaged.(e) R = 3/0.020 = 150 Ω.
Thinking further questions
1 Temperature and moisture sensors.
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2 (a) The voltage is too high. (b) Use a relay between the logic gate and thelamp.
3 (a) Light (LDR) and temperature (thermistor) sensors.(b) Heating runs off the mains electricity supply so will be 230 V, much
too high for a logic gate. 4 (a) I = V/R = 3.5/175 = 0.02 A(20 mA).
(b) R = V/I = 1.5/0.02 = 75 Ω.
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In-text questions
(a) Thermistor.(b) Bell.
Thinking further questions
1 (i) thermistor (ii) buzzer/bell (iii) OR gate. 2 living room bedroom pump
off off offoff on onon off onon on oninput – thermostats, processor – OR gate, output – hot water pump.
3 door 1 door 2 alarmclosed closed offclosed open soundsopen closed soundsopen open soundsprocessor – OR gate
4 Inputs – switch which is closed when seat belt is done up, pressure switchwhich is closed when seat is occupied.Output – alarm in form of bell/buzzer/indicator lamp on dashboard.seat belt seat alarm seat belt seat alarmopen open off 0 0 0open closed on 0 1 1closed open off 1 0 0closed closed off 1 1 0Need to add a NOT gate to the seat circuit; this gives the inverse of an ORgate, so place another NOT gate in the output circuit.seat belt seat seat NOT OR out NOT0 0 1 1 00 1 0 0 11 0 1 1 01 1 0 1 0
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In-text questions
(a) Check agreement with truth table.(b) Check agreement with truth table.(c) C D
1 01 10 00 0
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(d) To detect body heat.(e) To reverse the light sensor output, making it ‘high’ in the dark.(f) Lamp needs larger current than the logic gate.(g) C D
1 01 01 00 1
(h) (see diagram)
Thinking further questions
1 NOT 2 A B C D out
0 0 0 1 00 1 1 0 01 0 1 1 1
1 1 1 0 0
3 (see diagram)
4 A = 1 B = 0 C = 0
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In-text questions
(a) Bistable unit using two NAND gates.(b) Latch using two NAND gates.(c) NOR inputs output
0 0 10 1 01 0 01 1 0
Use of NOR gate truth table to checklogic of bistable.
(d) Use of NOR gate truth table to checklogic of latch.
(e) Make R high momentarily.
Thinking further questions
1 Input R must go high.
2 NAND 1 R1 other input 1
NAND 2 S1 other input 0
Output 1
R connected to low voltage, output becomes 0.
3 Connect input S of a latch to the doorbell so that S goes high if the bell rings.This will set the latch until Steve resets it.
4 Latch circuit with S connected to the ‘on’ switch and R to the ‘off’ switch.
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In-text questions
(a) 4 V.(b) Decreases.
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1(1)
1(0)
1(0)
0S (1)
1(0) 1
(1)1
(1)0R
P
Q
1(0)
1(1)
0S
1(1) 1
(0)1(0)0
(1)Rout
LDR
thermistor
bell
Pressurepad 1
Pressurepad 2
Lightsensor
alarm
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(c) As R1 increases, voltage across it increases, output voltage decreases.(d) To switch off lamp when it becomes light.(e) Switch on lamp when it gets light.(f) Reverse positions of thermistor and resistor.(g) 2 V.
Thinking further questions
1 dark low
light high
2 Output voltage = 5 V at A decreasing to 0 V at B
3
4 (i) 1V (ii) 160 ohms (iii) V across BC increases; V across AB decreases
Spread 1.7
In-text questions
(a) VR
R RVout
LDRin=
+
(b) Reverse positions of thermistor and resistor, R.(c) Reverse positions of thermistor and resistor, R on top input to AND
gate, change AND gate for OR gate.(d) Decrease.
Thinking further questions
1 (a) A B C (b) AND gate (c) A B C During the day the LED doesdark 0 0 0 light 0 0 0 not glow whether S is pressed
0 1 0 0 1 0 or not. LED comes on whenlight 1 0 0 dark 1 0 0 it is dark but goes out if S is
1 1 1 1 1 1 pressed. 2 (a) To switch on a large current to operate the buzzer and stop the
machine.(b) A B C BUZZER
0 0 0 00 1 1 11 0 1 11 1 1 1Buzzer sounds when light fails to reach one or both LDRs, i.e., if barsare too long.
(c) NAND gate, so buzzer sounds, when light reaches both LDRs.
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45
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Electronics and control
Answers
1 (a) low (b) high (c) low. 3
2 (a) 0 0 0 (b) AND.
0 1 0
1 0 0 (c) E.g. Seat belt warning system, safety system for1 1 1 opening a safe in a bank. 4
3 (a) LDR and resistor connected as a potential divider with a voltmeter across the resistor. 3
(b) In the light the resistance of the LDR is low, so the voltage across it is low thereforethe voltage across the resistor, and the voltmeter reading, are high. When the lightintensity is less, the voltage across the LDR increases and the voltmeter readingdecreases. 3
(c) Read voltmeter for known light intensities; and mark scale. 2
4 Record and play buttons as inputs to AND gate, start switch connected to output. 4
5 D E F G
1 1 1 0
0 1 1 0
1 1 0 1
0 0 1 1
1 1 0 1
0 1 1 0
1 1 1 0
0 0 1 1 4
6 (a) (i) in dark room (ii) on outside of door. 2
(b) V at X = (1800/2000) × 6 = 5.4 V 3
(c) Yes, large voltage across it. 2
(d) New V at X = (1800/2000 000) × 6 = 5.4 × 10–5 V, very small so LED not on. 4
(e) (i) Mains lamp requires a much higher voltage than the LED. 1
(ii) Relay placed between X and mains lamp. Low voltage from X switches on relaywhich in turn switches on a large mains voltage for the lamp. 3
7 (a) AND gate. 1
(b) Output of AND gate not large enough to power alarm; relay used to switch on alarge voltage supply for alarm. 2
(c) Alarm stops as one input to AND gate now low. 2
(d) (i) A circuit in which the output is locked into one state, high or low, until it is reset. 2
(ii) Alarm will keep ringing even when a burglar steps off the doormat. 2
(iii) (see diagrams – figs 49, 50). 6
8 (a) Low power, less dispersion/emits light of a single colour. 2
(b) Low power so less energy wasted. 2
(c) (i) To prevent too large a current damaging the LED. 2
(ii) V across R = 5 – 1.7 = 3.3 V, R = 3.3 V/20 mA = 165 ohms. 3
(d) (i) Large reverse voltage when reverse biased. 2
(ii) Diode in parallel with LED and facing the opposite way,
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diode conducts better than LED when LED is reversebiased so current goes through diode. 4
(e) (i) LED – light emitted when diode conducts a current,
photodiode – current produced when light shines on it,
arrow directions on symbols show light away from ortowards the diode symbol. 3
(ii) Straight line through the origin. 2
(iii) In the light; low resistance so current is high. 3
(iv) Smallest output voltage = 10–9 A × 106 Ω = 10–3 V (1 mV). 3
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Processing waves
Introduction spread
In-text questions
(a)
(b) Equal to, less than, greater than.
(c) A more dense than B, angle of refraction > angle of incidence, B more dense than C,angle of refraction > angle of incidence, A glass, B water, C air.
(d) (i) 5 Hz.
(ii) Speed = frequency × wavelength, 5 × 0.3 = 1.5 m/s (150 cm/s).
Spread 2.1
In-text questions
(a) 300 000 000/200 000 000 = 1.5.(b) 1.5, same.
(c) Refraction at first surface, dispersion at first surface, refraction at second surface,further dispersion at second surface, red → violet (red refracted least).
Thinking further questions
1 (a) Calculation of sine i – 0.174 0.342 0.500 0.643 0.766 0.866 0.940calculation of since r – 0.122 0.259 0.375 0.485 0.574 0.616 0.707axes labelled, suitable scale, points correctly plotted.
(b) Straight line, through origin, omitting anomalous point.
(c) 38, 41.
(d) Slope of graph used, 1.33.
(e) 300 000 000/1.33 = 226 000 000 m/s.
2 Refractive index = sine 90/sine c, sine c = sine 90/refractive index.
Glass sine c = 1/1.5 = 0.6667, c = 41.8°.
Water sine c = 1/1.3 = 0.7692, c = 50.3°.
Spread 2.2
In-text questions
(a) Light from distant object almost parallel, to pass through focal point.
Thinking further questions
1 (a) 75 mm.
(b) Nothing.
2 (a) Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f, raythrough optical centre undeviated, image is at 2f, real, inverted, same size.
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wavelengthamplitude
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(b) Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f, raythrough optical centre undeviated, image is beyond 2f, real, inverted, magnified.
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In-text questions
(a) Ray diagram with object well beyond 2f, second ray diagram with object closer to lensbut image in same place, comment on how lens moved further away from film.
(b) Suitable explanation involving timing of beam, echo principle.
(c) To make image right way up.
(d) Stop light being ‘wasted’/make image brighter.
(e) Focal length, light parallel after passing through lens.
Thinking further questions
1 (a) Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f, raythrough optical centre undeviated, image is at 180 cm.
(b) Decreased.
(c) Larger.
2 (a) Lens only move a short distance in and out for the range considered.
(b) Image becomes blurred.
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In-text questions
(a) (i) 2.23, 1.62, 1.35, 1.18, 1.07.
(ii) Axes labelled, suitable scale, points correctly plotted, smooth curve.
(iii) Greater mass reduces frequency.
Thinking further questions
1 Alters the wind flow so not all in same direction at same speed, reduces chance of resonance.
Spread 2.5
In-text questions
(a) Transverse.
(b) 2.4 m.
(c) 523.2, 784.8.
Thinking further questions
1 Mid-point produces note with one antinode at mid point, quarter way along producesnote with two antinodes at ¼ and ¾ along length, double the frequency.
2 Axes labelled, suitable scale, points plotted, straight line, passing through origin.
Spread 2.6
In-text questions
(a) 1288 mm.
(b) Open tube has antinode at each end, closed tube has node at one end.
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(c) Closed pipe has antinode at open end, node, another antinode, node at closed end.
Open pipe has antinode at open end, node, another antinode, another node,antinode at closed end.
Thinking further questions
1 Pitch gets higher.
2 l/f calculated as 0.00390, 0.00347, 0.00313, 0.00293, 0.00260, 0.00234, 0.00208, 0.00195.
calculated as 1288, 1144, 1032, 968, 860, 772, 688, 644 mm.
Axes labelled, suitable scale, points correctly plotted, straight line, through origin,
slope = 330 000 mm/s (330 m/s), speed of sound.
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In-text questions
(a) = 330/256 = 1.29 m, whole wavelength difference at X, so 1.29 m.
(b) ½ wavelength difference at Y, so 0.64 m.
(c) 446 Hz, tightening string increases frequency, increasing beat frequency meansgetting further away from tuning fork frequency.
(d) Wavelength of microwaves much larger.
Thinking further questions
1 Wavelength of the light used is very short, large distance needed to make the distance ofband from central large enough to measure.
Spread 2.8
In-text questions
(a) Wave.
(b) They are undeviated, no diffraction occurs.
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Processing waves
Answers
1 A – false, B – false, C – true, D – false, E – true, F – true, G – false. 7
2 300 000/1.2, 250 000 m/s. 2
3 (a) Infrared. 1
(b) Ultraviolet. 1
4 Suitable scale, 2f and f correctly positioned, ray parallel to axis passing through f,
Ray through optical centre undeviated, image at 13 cm – 14 cm, real, inverted,3 cm – 3.5 cm tall. 8
5 Move it towards film. 2
6 (a) Parallel rays from Sun, focused onto paper. 2
(b) 35 cm. 1
7 5 cm, shortest focal length. 2
8 Refraction at both surfaces of first lens, refraction at both surfaces of second lens,focused on retina. 3
9 In step could lead to forced vibration, at resonant frequency bridge vibrates and collapses. 3
10 (a) Thinner string produces higher note. 1
(b) Shorten length, increase tension. 2
(c) Different quality or shape of note. 1
11 = 4 × 25.8 = 103.2 cm = 1.032 m, f = v/ = 330/1.032 = 320 Hz. 3
12 Distance from car to radio masts changing.
When path difference equal to whole wavelengths constructive interference and louder,when path difference equal to odd half wavelengths destructive interference and quieter. 3
13 (a) Reflected light is polarised in one direction. 1
(b) Only allow light vibrating in one direction through, at right angles to reflectedlight’s vibration. 2
(c) Transmitted light not polarised, some vibration in same direction as polarising filter. 2
(d) Particle does not vibrate, waves vibrate, particle would go through filter, wavewould not go through filter at right angles, polarisation supports wave behaviour. 5
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More about forces and energy
Introduction spread
In-text questions
(a) Distance from pivot to man is large so force required is small for agiven moment.
(b) 8.33 m/s.(c) 30 m/s.(d) 750 N.(e) Backward force is greater than forward force, force down greater than
force up.(f) (i) 240 000 J.
(ii) 4000 N.(g) Air resistance increases as velocity increases. Eventually air resistance
force upwards is equal to weight of parachutist downwards so velocitybecomes constant – terminal velocity.
(h) Double glazing, loft insulation, lagging hot water tank, cavity wallinsulation, carpets/curtains… (any three).
(i) 64%.
Spread 3.1
In-text questions
(a) 1.25 m/s2.(b) 2 m/s2.(c) (i) Graph – line through (2, 0) of gradient –10 cuts velocity axis at (0,20)
and (4, –20), maximum height = 20 m.(ii) Displacement = zero.(iii) Positive and negative areas of graph are equal.
(d) s =( ( ))u u at t+ +
2s = ut + 1
2at2
v + u = 2s/t v – u = at (v + u)(v – u) = 2s/t × at = 2as v2 = u2 + 2as(e) 60 m/s, 900 m.(f) (i) 7.2 m (ii) 1.2 s (iii) 2.4 s.
Thinking further questions
1 Steady acceleration of –0.5 m/s2, time to stop = 100 s. 2 2 m/s2. 3 576 m. 4 (a) 5 s, (b) 50 m/s, (c) 11.25 m/s.
Spread 3.2
In-text questions
(a) (i) 15 m (ii) 30 m (iii) 60 m.(b) Check values on graph.(c) Both fall the same vertical distance each second.(d) Same time as before.(e) It would go twice as far horizontally in each second.(f) Less than 45° – large horizontal component of velocity but short time
of flight (does not rise very high); more than 45° – small horizontalcomponent of velocity but long time of flight. 45° is half-way between0 and 90°, giving maximum range.
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Thinking further questions
1 Gravity pulls the dart downwards with an acceleration of 10 m/s2.Dart follows parabolic path.
2 0.5 s. 3 (a) 3 s (b) 45 m. 4 1000 m.
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In-text questions
(a) 20 000 kg m/s.(b) 520 kg m/s.(c) 8 m/s, 0.8 m/s.(d) 15 m/s.(e) 0.6 m/s to right.
Thinking further questions
1 Since there was zero momentum before Chris moved, his momentumtowards the jetty equals the momentum of the boat away from the jetty.
2 400 m/s. 3 2 × 107m/s. 4 F = 250 N when she bends her knees, 25 000 N when she does not.
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In-text questions
(a) Mass decreases as fuel is used up, gravitational field strengthdecreases as height increases.
(b) No forces acting on the rocket so it will maintain a constant velocity.(c) 2 m/s.
Thinking further questions
1 A rocket carries its own oxygen supply, a jet plane does not.2 (a) S answer. The water escaping from the open end of the bottle gives a
force on the bottle in the opposite direction, so it rises (Newton’sthird law).H answer. The momentum of the water downwards is equal to themomentum of the rocket upwards, so the rocket rises.
(b) (i) 50 m/s2 (ii) Acceleration decreases because the mass of waterejected per second and its velocity decreases. The unbalanced force (ormomentum of the rocket) decreases at a faster rate than accounted forby the decrease in mass, so the acceleration decreases.
3 No momentum before the balloon is released, so the momentum of the airmolecules in one direction is equal to the momentum of the balloon in theopposite direction.
4 1 280 000 N.
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Spread 3.5
In-text questions
(a) The cars have much more kinetic energy to be converted into otherforms on impact. The deceleration is greater when the speed is higher,so the force on the occupants is greater.
(b) The person would be stopped very quickly causing a large decelerationand so a bigger force.
(c) Large area so that the pressure (= force/area) on the child’s body isless, reducing the risk of serious injury.
Thinking further questions
1 (a) To stop you being thrown forward at high speed, possibly through thewindscreen.
(b) So that back seat passengers cannot be thrown forward and strike thedriver.
2 The front and rear sections are designed to crumple in an accident,stopping the car more slowly and reducing the force on the occupants –crumple zones. The passenger compartment is very strong so that thepassengers are not crushed.
3 The rapid deceleration that occurs in an accident inflates the airbag veryrapidly. This protects the driver from injuries caused by the steering wheeletc. being forced against him.
4 (a) 8 m/s.(b) 200 000 J.(c) 80 000 J.(d) 120 000 J.(e) 8400 J.(f) 4200 N. Suitable comment – e.g. if she had moved a shorter
distance/the seat belt had been tighter, the force on her would havebeen greater.
Spread 3.6
In-text questions
(a) 1008 000 J.(b) 91 200 J.(c) 601 200 J.(d) Aluminium has a high specific heat capacity, so requires more energy
to heat it than other metals such as copper, making it more expensiveto use. Also it is not such a good conductor of heat as copper so itwould take longer for the water to be heated.
(e) Too high.
Thinking further questions
1 iron (9000 J) [lead – 7560 J]. 2 Water has a very high SHC so can absorb a large amount of energy without
raising its temperature very much. 3 Treacle has a higher SHC than sponge so absorbs a lot more energy.
It therefore takes longer for its temperature to fall on cooling as it hasmore energy to lose.
4 500 J/kg°C.
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In-text questions
(a) Reduces energy wasted due to friction.(b) Temperature is related to molecular movement. Water molecules are
moving faster at the bottom of the waterfall than at the top, so thewater temperature is higher.
(c) 600 000 J.(d) 420 000 J.(e) 0.2°C.(f) Temperature rise unchanged. GPE and so thermal energy produced per
second halved, but energy required to heat water halved also. 70% ofmgh = mc so m’s cancel.
(g) 45%.
Thinking further questions
1 32% Energy wasted as heat (due to friction), sound etc. 2 energy source advantages disadvantages
solar energy fuel is free Sun does not always shineuseful in hot countries cover large area to produce power
equivalent to a small power stationwind energy fuel is free wind does not always blow
does not pollute atmosphere visual and noise pollutioncover large area to produce powerequivalent to a small power station
geothermal free energy only possible in certain placesnon polluting expensive to drill down several km
3 1600 W. 4 Any relevant points.
e.g. petrol engine
fuel readily availablegreater range on full tankhigh top speedpollutes environmentnoisy
electric motor
need recharging facilitylimited rangelower top speedlittle/no pollution (but pollution at power station)quiet
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More about forces and energy
Answers
1 (a) Acceleration (b) temperature (c) parabola (d) rocket. 4
2 (a) v = u + at, t = (v – u)/a = 50/2.5 = 20 s (or acceleration = velocity change/time). 3
(b) (i) v2 = u2 + 2as, 2500 = 0 ± (2 × 2.5 × s), s = 500 m. 3
(ii) motorist travels 40 × 20 = 800m. 2
(c) 5
(d) Area under graph for P from t = 0 to t = 20 s = ½ 50 × 20 = 500 m. 2
(e) When they meet, after time T, the area under each graph is the same.
40 × T = 500 + 50 (T – 20), T = 50 s. 4
3 (a) Q = mc = 2 × 380 × 500 = 380 000 J. 3
(b) (i) Q = mc2 = 70 × 800 × 30 = 1680 000 J. 3
(ii) Concrete stores more energy as it takes more energy to heat it up/has greater SHC.This means it releases more energy as it cools down. 3
(c) E.g. Low density, low thermal conductivity, traps air, inert, not flammable.
4 (a) KE = ½ mv2 = ½ × 80 × 202 = 16 000 J. 3
(b) WD = KE lost, F × 160 = 16000, F = 100 N. 3
(c) F × 1.6 = 16 000, F = 10 000 N. 2
(d) 4 times bigger/F becomes 40 000 N.
v doubled so KE (= ½ mv2) increases 4 times, so braking force is 4 times bigger. 2
(e) Engine compartment crumples in an accident so the car stops more slowly and theforce on the occupants is less. Reference to F = ma or Ft = mv – mu. Passengercompartment strong so does not crumple. 3
5 (a) (i) Weight vertically downwards = 30 × 106 N, thrust vertically upwards = 33 × 106 N. 3
(ii) Resultant force = 3 × 106 N. 1
(iii) F = ma, 3 × 106
= 3 × 106 × a, a = 1 m/s2. 3
(b) (i) Mass lost = 14 000 × 2 × 60 = 1680 000 kg. 2
(ii) Mass after 2 minutes = 3 × 106 – 1.68 × 106 = 1.32 × 106 kg. 1
(iii) F = ma, 33 × 106 – 13.2 × 106 = 1.32 × 106 × a, a = 15 m/s2. 3
(iv) Gravitational field strength decreases with height. 1
6 (a) Renewable energy extracted from the environment; not used up, so always availableto us. E.g. wind, wave, tidal, HEP, solar, geothermal, biomass (any two).
Non-renewable – once they are used they are gone for ever. E.g. coal, gas, nuclear(any two). (4)
(b) Answers will depend on the examples given in (a).
Renewables – see Spread 7, question 2.
Non-renewables – advantages could include availability currently, small spaceoccupied for the amount of energy produced, well established technology.
Physics TBA3 Answers: end of teaching block
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Disadvantages could include pollution – acid rain, global warming, limited supplies.Nuclear – radiation hazards/accidents/decommissioning. 6
7 (a) 0.5 kg – energy = mcθ = 0.5 × 4200 × 80 = 168 000 J.
1.0 kg – energy = mcθ = 1.0 × 4200 × 80 = 336 000 J.
1.5 kg – energy = mcθ = 1.5 × 4200 × 80 = 504 000 J. 6
(b) 0.5 kg – efficiency = energy output/energy input × 100 = 168/200 × 100 = 84%.
1.0 kg – efficiency = energy output/energy input × 100 = 336/380 × 100 = 88%.
1.5 kg – efficiency = energy output/energy input × 100 = 504/540 × 100 = 93%. 6
(c) The energy required to heat the kettle stays the same. 2
(d) Energy required to heat the kettle/element, energy lost to surroundings. 2
(e) Energy transfer is very efficient, efficiency increases as the mass of water increases,as the energy used to heat the kettle, etc., becomes a smaller proportion of the totalenergy input. 3
8 (a) s = 12 at2 (u = 0) 0.128 = 1
2 × 10 × t2 t = 1.16 s 3
(b) Fiona is expecting the ruler to be dropped/is prepared to catch the ruler. 2
9 (a) Bends down/leans low, keeps arms close to body, wears streamlined clothes. 3
(b) Photocell and light source at either side of track to trigger an alarm when the lightbeam is broken before the starting gun is fired. 2
(c) Sufficient friction to prevent slipping, good water drainage/run off properties, nottoo rigid/’gives’ a little to prevent damage to knee joints (any two). 2
(d) Different events require footwear to keep friction low for speed, provide good anklesupport, have cushioned soles to reduce impact when jumping, for example. 2
(e) (i) Initial acceleration = velocity change/time = 12/2 = 6 m/s2. 3
(ii) Air resistance increases as velocity increases, eventually air resistance force isequal to the forward force, so there is no acceleration. 3
(f) (i) KE = ½ mv2 = ½ × 60 × 122 = 4320 J. 3
(ii) Power = energy transferred/time = 4320/2 = 2160 W. 3
(iii) Used to overcome resistance to motion, to maintain bodily functions, changedto thermal energy to keep the body warm, used to produce sweat. 3
(iv) Wear warmer/cooler clothes to keep body temperature constant, streamlineclothes/position of body to minimise air resistance, reduce friction with track(but not too much or runner will slip). 2
© Heinemann Educational 2001
Physics TBA3 Answers: end of teaching block
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