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Transcript of TKF Makalah Final
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ContentsOverview ................................................................................................................................... 2
Competence Standard : ........................................................................................................ 2
Basic Competence : ................................................................................................................... 2
Indicator : ................................................................................................................................. 2
Content .......................................................................................Error! Bookmark not defined.
Phenomenon: ........................................................................................................................ 4
How Lightning Works? ...................................................................................................... 4
How does light bulb work? .............................................................................................. 5
Concepts map ....................................................................................................................... 7
Description of Material ......................................................................................................... 8
Mini lab ............................................................................................................................... 19
Summarize .......................................................................................................................... 20
Evaluation ............................................................................................................................... 22
Assessment ......................................................................................................................... 29
References .............................................................................................................................. 32
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ELECTRICITY
Overview
In this paper will be discussed about electricity which is divided into static
electricity and dynamic electricity. In static electricity, will be discussed about electric
charge, conductor and insulator, electric charge induction, Coulombs Law, the electric field,
and electric potential. Meanwhile in dynamic electricity will be discussed about electric
current, voltage, electric resistance and Ohms Law, series and parallel circuit and
Kirchhoffs rules, electric energy, and electric power.
Competence Standard :understanding the concept of electricity and the application in daily life.
Basic Competence :3.1 Describing the electric charge to understanding the indication of static electric and the
daily life
3.2 Analyzing the experiment of dynamic electric in the circuit and the application in daily
life.
3.3 Describing the element work principle and the electric current and the application in
daily life.
3.4 Describing the connection of energy and electric power and the utilization in daily life.
Indicator :Based on basic competence above, wished student can:
1. Explain an object may be electric charge when it is rubbed2. Provide an example of event making an object charged with electricity and the process
through which it occurs in simple way
3. Explain electric field4. Explain electric potential
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5. Explain the concept of electric current and electric potential difference6. Make a series circuit and parallel circuit7. Find the difference in resistance of several material (conductor, semiconductor,
insulator)
8. Describe Kirchhoff first rules9. Calculate substitute resistance of series and potential electric circuits10.Explain the relationship between the electrical power, electrical energy, and its unit
(kWh and Joule)
11.Apply the concept of energy and the electrical power in the household based on thenumbers displayed in the kWh meter
12.Show the alteration of electrical energy into other form of energy13.Show some household tools that using electrical energy
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Material
Phenomenon:
Static Electricity
How Lightning Works?The formation of the initial storm cloud is the
initiating process to how it becomes so
charged. Its common knowledge that clouds
are formed by water droplets they condense
as they go higher in the air. These droplets
collide into one another, as they become
more condensed these collisions become
vigorous and eventually lead to electrons
being knocked off and falling to the lower end
of the cloud while the protons continue up to the top. This falling of electrons creates a
very negative bottom of the cloud and a positive top; this in turn causes an electric field to
form in the atmosphere around the cloud. The negative bottom of the cloud becomes
strong enough to repel electrons on the earths surface causing the surface to become
positively charged. This extreme attraction is
the layout of how lightning forms.
Now that there is a huge charge
separation the electric field surrounding the
cloud starts to break down the air, as in
lengthening the space between the electrons
and the protons, this process is actually ionizing
the air. The ionization that occurs leaves many
paths that the lightning can take to try and even
out the charge separation between the cloud
and the ground. These paths are referred to as leaders or step leaders. The leaders find the
Source: www.123rf.com
source: www.uwec.edu
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easiest way through to the opposite charge, which
means that not all cloud-to-ground lightning is in fact
cloud to the ground some could actually be the
ground sending an electrical current up to the cloud.
When a spot on the earths surface prepares for an
electrical discharge the positive places on the ground
send out streamers that are basically flagging the
object as being one that is in position for easy access.
These streamers have actually been known to be
purplish or even greenish in color, they are most likely
to form on tall pointed objects, but it is not out of the question for them to form on
humans. The final step in the occurrence of lightning is the meeting of the leader and
streamer, now the charges flow through the path with no mercy for what or whom it
strikes.
Dynamics Electricity
How does light bulb work?Electricity flows through a thin wire in the light
bulb called the filament. The filament used in a
bulb has a property called "resistance."
Resistance is the amount of friction that an
object will put against electricity flowing
through it. A filament has a lot of resistance to
electricity. Therefore as a result of this, the
filament heats up and starts glowing, converting
electrical energy to light energy. This is because
the resistances heat up when electrical current
runs through them.
Source: www.blogto.com
Source www.en.wikibooks.org
http://www.en.wikibooks.org/http://www.en.wikibooks.org/http://www.en.wikibooks.org/ -
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Concepts map
Electric
potential
Electric
fieldelectric
charge
induction
Currentresistance
voltage
Electric
energyElectricpower
Closed
circuit
Electric
conductivit
Electric charge
insulatorconductor
Static Electric Dynamic electric
electricity
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Description of Material
Electricity
Many of us take for granted the role that electricity has in our lives. Devices such as
televisions, CD players, computers, and now even telephones all depend on a constant
supply of electricity to our household. We will examine the nature of electricity, how it is
generated, and the way in which it is linked to technological development. So we will
discuss about electricity.
1. Statics electricity
Why does walking across a carpeted floor and then
touching something sometimes result in a shock?
The answer has to do with electric charge. Atoms
contain particles called protons, neutrons, and
electrons, as shown in Figure 1. Protons and
electrons have electric charge, and neutrons have
no electric charge. There are two types of electric
charge. Protons have positive electric charge and
electrons have negative electric charge. The amount
of positive charge on a proton equals the amount of negative charge on an
electron. An atom contains equal numbers of protons and electrons, so the
positive and negative charges cancel out and an atom has no net electric
charge. Objects with no net charge are said to be electrically neutral.
Figure 1. The center of an
atom contains protons
(orange) and neutrons
(blue). Electrons (red) swarm
around the atoms center.
Source Glencoe Science
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a. Electric ChargeThere are two kind of charges,
positive charge and negative charges.
Figure 2 shows that unlike charges
attract other, and like charges repel
each other. The force between electric
charges also depends on the distance
between charges. The force decreases
as the charges get farther apart.
Thelaw of conservation of charge, charge can be transferred from object to object,
but it cannot be created or destroyed. Whenever an object becomes charged, electric
charges have moved from one place to another.
.
b. Conductors and insulatorsIf you have two metal balls. One is charged and the other is not. If you put an iron
nail in a given way so that they are touching one another, it is found that the ball previously
uncharged becomes charged in short time. If you connect both balls with a wood, the
uncharged ball remains. Object like the iron nail are referred to electric conductors. On the
other hand object like wood and rubber is called non-conductor or insulator. Shown figure 3
Figure 3. (a)Charged and neutral metal balls; (b) Both balls charged; (c) almost no charged
conducted
Source The essentials of physics
Figure 2. Positive and negative charges exert forces
on each other.
Source Glencoe Science
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Conductors A material in which electrons are able to move easily is a conductor. Electrons
on your shoes repel each other and some are pushed onto your skin. Because your skin is a
better conductor than your shoes, the electrons spread over your skin, including your hand.
The best electrical conductors are metals. The atoms in metals have electrons that are able
to move easily through the material. Electric wires usually are made of copper because
copper metal is one of the best conductors.
Insulators A material in which electrons are not able to move easily is an insulator.
Electrons are held tightly to atoms in insulators. Most plastics are insulators. The plastic
coating around electric wires, Other good insulators are wood, rubber, and glass.
c. The creation and transfer of changeCharging by Friction
When two different
substance are rubbed together,
there is a net transfer of electron
from one material to the other.
When rubbed together, the energy
of friction moves electrons from
the object that has the weakest
force of attraction. Show figure 4
Charging by Contact
Once something is charged either positively or negatively, it tends to lose its excess
charge to other object if they come into contact. Point out that excess electrons in a
negatively charged object move to a neutral body, leaving it with a negative charge Figure 5
(a). A positively charged object will draw electrons out of a neutral object, leaving it
positively charged (b).
Figure 4.
Source Physics concept and connection
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Charging by Induction
When a charged
object is brought close to an
object without physical
contact, the charged object
will induce a movement of
electrons in the uncharged
object. If the object to be
charged is attached to a
grounding source. The object
will take on or off-load
electrons to the ground.
Shown Figure 6
d. Coulombs Lawelectric charge gives another electric charge a force. The experiment carried out
concluded that the amount of repulsive or attractive force between two electric-charged
object was proportional to the power of each object and inversely proportional to distance
charge of both object.
F = k.
Figure 5. Charging by contact with a charged glass rod
Source Physics concepts and connections
Figure 6. Charging an electroscope negatively by induction
Source Physics concepts and connections
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Where, q1 and q2 = electric charge of each object (C)
F = attractive or repulsive force (N)
r = distance of both object
K = coulomb constant (k = 9x109 Nm2/C2)
e. The Electric FieldThe electric field is the area around an electric-charged object that is still under the
influence of electric force. The electric field surrounding an electric-charged object can be
illustrated as a force line moving from the positive to negative charges.
Watch the illustration of electric field line above shown figure 7. The electric field line
follows the following conditions.
1. The field lines display an electric field direction.2. Those lines are illustrated in such a way that the magnitude of electric field is
proportional to the number of the lines passing through the perpendicular area
upon them. The lines is closer, the stronger the related field.
3. The electric field lines begin from the positive and end at the negative charges. Itsnumber, however, from the beginning to the end is proportional to the magnitude
of charge.
f. Electric PotentialCharge does not flow on its own. We saw previously that excess of any one charge
causes a force of repulsion. A complete circuit also allows the excess charge to see a region
of charge deficit at the power supply.
Figure 7.
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In the same way that the bicycle in fig 16.6 possesses gravitational potential energy
at different heights in a gravitational field, an electric charge has a certain amount of
electrical potential energy because of the electric field set up by the power supply.
Work had to be done on the bicycle to increase its gravitational potential energy. Similarly
for the charge in the circuit. Work is done by the power supply to increase the electrical
potential energy of each coulomb of charge from a low to a high values. As the charge flows
through the load, its energy decreases.
Notes:
One volts (V) is the electric potential difference between two points if one joule of work (J) is
required to move one coulomb (C) of charge between the points.
In the material above, we have studied about electrostatics, which is electricity at rest. In
electrostatics the charges just do a simple move and sometime they need a certain
treatment to make the charge move from an object to others. But, how if the charges now
not just move instead flow continously? Is it seems impossible? But the fact is we can
turning on the light, watching TV, etc because of the flowing charge. How could it be? It will
be clear when we have studied about dynamics electricity below
The electrical potential energy for each coulomb of charge in a circuit is called
the electric potential difference (V).
V=
Where is the energy required to increase the electric potential of a charge Q.
potential difference is often called voltage
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2. Dynamics electricityIn the material above, we have studied about electrostatics, which is electricity at
rest. In electrostatics the charges just do a simple move and sometime they need a certain
treatment to make the charge move from an object to others. But, how if the charges now
not just move instead flow continously? Is it seems impossible? But the fact is we can
turning on the light, watching TV, etc because of the flowing charge. How could it be? It will
be clear when we have studied about dynamics electricity below.
a. Current and Voltage DifferenceWhen a spark jumps between your hand and a metal doorknob, electric charges
move quickly from one place to another. The net movement of electric charges in a single
direction is an electric current. In a metal wire, or any material, electrons are in constant
motion in all directions. As a result, there is no net movement of electrons in one direction.
However, when an electric current flows in the wire, electrons continue their random
movement, but they also drift in the direction that the current flows.
Voltage Difference The movement of an electron in an
electric current is similar to a ball bouncing down a flight of
stairs. Even though the ball changes direction when it
strikes a stair, the net motion of the ball is downward. The
downward motion of the ball is caused by the force of
gravity. When a current flows, the net movement of
electric charges is caused by an electric force acting on the
charges. In some ways, the electric force that causes
charges to flow is similar to the force acting on the water in
a pipe. Water flows from higher pressure to lowerpressure, as shown in Figure 8. In a similar way, electric
charge flows from higher voltage to lower voltage. A
voltage difference is related to the force that causes
Figure 8. Electric forces in
a material cause electric
current to flow, just as forces in
the water cause water to flow.
Source Glencoe
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electric charges to flow. Voltage difference is measured in volts.
b. Resistance and Ohms LawThe amount of current flow in a circuit, and therefore the amount of energy
transferred to any useful device, depends on two things: (1) the potential difference of the
power supply and (2) the nature of the pathway
through the loads that are using the electric
potential energy. The push on the charge
(potential difference) is the same, but the pathway
are very different. The overall result is that the
more difficult the path, the more opposite there is
to flow. The measure of this opposition to flow is
called electrical resistance. The illustrated in Fig.
9(a) and schematized in 9(b) allows us to
experiment with the electrical potential across a
load.
Current is a straight line and the slope of the graph, the
ratio, is constant.
Therefore, the slope and the
ratio must represent the resistance of the load because the
resistance remained unchanged in the experiment.
Where R is the resistance in Ohm ()
V is the potential difference in volts (V)
I is the current in Ampere (A)
c. Series and Parallel CircuitTo related current, potential difference and resistance in simple circuit, we can
examine the different ways in which those circuits can be combined. The two simplest ways
R =
Figure 9.
Source Physics concepts and
connections
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to connect conductors and loads are illustrated in fig.10. in
a series circuit, the loads are connected one after another
in a single path, whereas in a parallel circuit.
Each arrangement affects the way in which
potential difference and current act in the various parts of
the circuit. Gustav Robert Kirchhoff studied the way each
of the circuit parameters behaved in series and parallel
circuits. His research led to the publication of the laws of
both current and voltage, called Kirchhoffs laws.
In Fig. 11, three branches meet at one junction
point and two branches leaves another junction point so
that I1 + I2 + I3 = IT = I4 + I5.
In fig.16.15, the potential increase, VT is equivalent to
the sum of all the potential losses so that VT = V1 + V2 +
V3. Kirchhoffs law are perpendicular applications ofthelaw of conservation of electric charge and the
conservation of energy. In other words, in any circuit,
there is no net gain or loss of electric charge of energy.
Kirchhoffs current law The total amount of current into a junction point of a
circuit equals the total current that flows out of that same junction.
Kirchhoffs voltage law The total of all
electrical potential decreases in any
complete circuit loop is equal to any
potential increases in that circuit loop.
Figure 10. Series and parallel
circuit
Source Physics concepts and
connnections
Figure 11. An Illustration of
Kirchhoffs current law
Source Physics concepts and
connections
Figure 12. An Illustration of
Kirchhoffs voltage law
Source Physics concepts and
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Resistance in Series
we find that all current must first pass through resistor 1, then 2, and so on. The voltage
drops across each resistor. The sum of the voltage drops gives the overall voltage drop in
the circuit.
From Kirchhoffs law, VT = V1 + V2 + V3
From Ohms law, ITRT = I1R1 + I2R2 + I3R3
But from Kirchhoffs law, IT = I1 = I2 = I3
The currents factor out; IRT = IR1 + IR2 + IR3
Therefore, RT = R1 + R2 + R3
For the more general case where you have more thanthree resistors, the equation
can be generalized as
RT = R1 + R2 + R3 + RN
Where N is the total number of series resistors in the circuit.
Resistance in Parallel
we find that the total current must split and distribute itself among all of the available
circuit paths.
From Kirchhoffs law, IT = I1 + I2 + I3
From Ohms law,
=
+
+
But from Kirchhoffs law, VT = V1 = V2 = V3 = V
The voltage factor out;
=
+
+
Therefore,
=
+
+
For the more general case where you have more than three resistors, the equation can be
generalized to
=
+
+
+
Where N is the total number of parallel resistors in the circuit.
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d. Electric EnergyIf you are holding an electric light bulb which is switched on, sometimes later the
bulb will be felt hotter and hotter. It is because some of the electric energy is converted into
light energy and heat energy. It is found that the bigger potential difference and current
strength produces the bigger heat energy. In contrast, the smaller potential difference and
the strength current, produces smaller heat energy. It means, can say that the amount of
the heat energy is proportional to the potential difference and the current strength.
Or
Where, W = electric energy, in joule
V = potential difference, in volt
I = current strength, in ampere
R = resistor, in Ohm
t = time, in second
e. Electric PowerThe reason that electricity is so useful is that electrical energy is converted easily to other
types of energy. For example, electrical energy is converted to mechanical energy as the
blades of a fan rotate to cool you. Electrical energy is converted to light energy in light
bulbs. A hair dryer changes electrical energy into thermal energy. The rate at which
electrical energy is converted to another form of energy is the electric power. Appliances of
electric power often are labeled with a power rating that describes how much power the
appliance uses. The electric power used depends on the voltage difference and the current.
Where, P = electric power, in watt
W = electric energy, in joule
V = voltage difference, in volt
I = electric current, in ampere
W = I2
. R . t
P = V . I P =
W = V . I . t
Or
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Mini labInvestigating Electric Charge Fiture
A.B.C.D.
E.F.
G.H.I.J.K.L.M.N.O.P.Q.R.S.T.
U.V.
Prepare plastic combs, glass rods,
wool, silk, prop and string. Rub
two plastic combs to the wool.
Then hang one of the combs on
the prop by using string. Put the
other comb close to the hanging
one. What happen to both
combs? Then what happen if now
you rub two glass rods to the silk
and then hang one of the rods
on the prop by using string and
Put the other comb close to the
hanging one? Repeat it by
rubbing one of the combs to the
wool and one of the glass rods to
the silk. Hang the comb on the
prop by using string and put theglass rod close to it.
Observe what is happening to the
combs?
Explain what do you get from this
experiment and analyze how
could it be?!!
Materials:
-2 plastic combs -silk -prop
- 2 glass rods -wool -string
3. Rub two rub two glass rods totake silk. Then hang one of the
glass rods on the prop by using
string. Put the other glass rods
close to the hanging one
4. Observe what is happening toboth robs and write the
description in the table
1. Rub two plastic combs to thewool. Then hang one of the
combs on the prop by using
string. Put the other comb close
to the hanging one
2. Observe what is happening toboth combs and write the
description in the table
5. Repeat by rubbing one of thecombs to the wool and one of the
glass rods to the silk. Hang the
comb on the prop by using string
and put the glass rod close to it
6. Observe what is happening tocomb and write the description in
the table
Procedure:
Table of observation result
activitythe object
hung
the object put close to
the hungdescription
a
b
c
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Summarize
Static electric charge occurs due to the pressure of electron existing within each ofsubstances atom
An electron constitutes small particle in a negative-charge atom The electron released from an atom causes an object to have positive charge,
conversely, when the electron number is exceeding, it make it negative-charged
Electric charge of a similar rejects each other and those not of a similar attract oneto other
A material in which electrons are able to move easily is a conductor. A material inwhich electrons are not able to move easily is an insulator
The separation of electron from its atom can be done by rubbing an object toanother object, such as the case of rubbing plastics to wool and glass to silk.
The magnitude of rejecting or attracting force between two objects with electriccharge can be determined using Coulombs law. The formula for Coulombs law is
F = k.
The electric field is the area around an electric-charged object that is still under theinfluence of electric force.
The electrical potential energy for each coulomb of charge in a circuit is called theelectric potential difference (V).
V=
The amount of electric charge flowing on a conductor in 1 second is referred tocurrent
A voltage difference is related to the force that causes electric charges to flow. The amount of current is proportional to the potential difference and inversely
proportional to the resistance (Ohms law), which is formulated as follow
R =
In resistance arranged in series, the amount of substitute resistance is equal to thesum of the set resistance and it is formulated
RT = R1 + R2 + R3 + RN
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In resistance arranged in parallel, the amount of substitute resistance is equal toreverse of sum reverse of the set resistances. It is formulated as follows
=
+
+
+
The electric energy has special quality compared to other form of energy for it iseasy to change into other form of energy.
The electric energy is proportional to the potential, current, and time. It isformulated as
W = I2
. R . t or W = V . I . t
The amount of electric energy used in each second is called electric power, W isformulated as
P =
or P = V . I
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Evaluation
A. Objective1) Coulomb force of charges is F. If the distance between the charges is made 2 times
from the initial, the coulomb force of those charges now is......... (C3)
a. F b. 2 F c. F d. 4FAnswer : (C)
Source : http://www.physicsclassroom.com
2)
What is the type of charge of C and D? (C4)
a. C = + and D = - c. Both C and D = -b. b. C = - and D = + d. Both C and D = +Answer : (A)
Source : http://www.physicsclassroom.com
3)A negatively-charged balloon is held above (without touching)
a neutral electroscope. (see figure beside) The presence of the
nearby balloon causes the needle of the electroscope to
deflect. The right type of excess charges on a, b, c, and d on the "polarized" neutral
electroscope is............. (C4)
a. a = + b = - c = + d = -b. a = - b = + c = - d =+
a
b
dc
http://www.physicsclassroom.com/http://www.physicsclassroom.com/http://www.physicsclassroom.com/http://www.physicsclassroom.com/ -
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c. a = + b = - c = - d = -d. a = - b = + c = + d =+Answer : (C)
Source : http://www.physicsclassroom.com
4) The V-I graph is given below:
If voltage is 4,5 volt, the current will be ............... Ampere. (C4)
a. 0,01 A b. 0,03 c. 0,27 d. 3,33Answer : (B)
Source: physics concepts and connections(2001)
5) The lamps in the figure below are all identic. Which is the brightest lamp? (C4)
a. A b. B c. C d. D
Answer : (D)
Source: physics concepts and connections(2001)
http://www.physicsclassroom.com/http://www.physicsclassroom.com/ -
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6) The amount of charge that passes through the light bulb in 2 second is 1,67 C. Findthe current in the bulb! (C3)
a.0,417 A b. 0,835 A c. 1,67 A d. 3,34 A
Answer : (B)
Source: physics concepts and connections(2001)
7) A coffee maker draws about 5,0 A of currents f0r 270 s using 1,6 x 105 J of energy.What is the potential difference across the coffee maker? (C3)
a. 0,08 V b. 119 V c. 2963 d. 2160 x 105Answer : (B)
Source: physics concepts and connections(2001)
8) A 200 m piece of aluminum wire has a resistance of 1,7 . What is the resistance ofa 50 m portion cut from it? (C3)
a. 0,15 b. 0,42 c. 2,35 d. 6,80 Answer : (B)
Source: physics concepts and connections(2001)
9)
What is the parallel equivalent resistance for a 25 , 40 , and a 10 resistor, wired
in parallel? (C3)
a. 0,16 b. 5 c. 6,1 d. 65 Answer : (C)
Source: physics concepts and connections(2001)
10)Calculate the power rating of a stereo amplifier if it is plugged into a standard 120 Voutlet and has a resistance of 120 ? (C3)
a. 0 W b. 1 W c. 120 W d. 14.400 WAnswer : (C)
Source: physics concepts and connections(2001)
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B. Essay1. A neutral conducting sphere is charged by induction using a positively-charged
balloon. What will be the charge of the following sphere in step e if steps a - d are
followed? (C5)
Explain how the object acquires this charge. Show the type and location of excess
charge on the conducting sphere in each step of the diagram.
Answer :
In b., the presence of the positively-charged balloon serves to polarize the sphere.
Electrons in the sphere are drawn towards the positively-charged balloon. This
leaves a separation of charge in the sphere, with the excess negative charge on the
left and the excess positive charge on the right.
In c., the sphere is touched to ground and electrons from the ground are drawn
upwards and into the right side of the sphere. It is the presence of the + charge on
the right side of the sphere which attracts these electrons to itself. At this point the
sphere is charged negatively.
In d., this excess negative charge is shown distributed on the left side of the sphere,
still drawn towards the positively-charged balloon.
In e,. the balloon is pulled away and there is a movement of electrons about the
sphere so that the excess negative charge is uniformly distributed.
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2. Construct electric field lines around the following configuration of charges. Includeat least six lines per charge. (C4)
a. b.
c. d.
Answer :
a. b. c. d.
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3. A house use 4 units 40W bulbs for 10 hours a day, a 150W TV for 8 hours a day, anda 60W fan 4 hours a day. If electricity prices are Rp 500, - per kWh, how much cost
to be paid for one month usage? (C3)
Answer :
W per day
Object W = n.p.t (Wh)
bulbs 4.10.40 = 1600
TV 1.150.8 = 1200
Fan 1.60.4 = 240
total W 3040 Wh
W per month = 30 x W per day
= 30 x 3040
= 91.200 Wh
= 91,2 kWh
Money paid = W per month x cost/kWh
= 91,2 kWh x Rp 500/kWh
= Rp 45.600,-
4. Figure above shows a simple series circuit. Use kirchhoffs voltage and current lawsto find the values of the missing voltage (V2) and current (I2) (C4)
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Answer:
VT = V1 + V2 + V3
So, V2 = VT - V1 - V3
= 100 V 30 V 30 V
= 40 V
IT = I1 + I2 + I3 = 10 A
5. Write your idea about a solution to avoid the strikes of lightning on the high buildingand how it works! (C6)
Answer:
Depend on student answers
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Assessment
Phsycomotorics assessment:
Give () according to student psychomotor
No AspectChecklist
yes No
1 Check all of the tools and materials before used
2 Rub the comb or rod glass to make them charged
3 Arrange the tools and materials such as design given in the minilab
4make the string and hanging object in statics condition before they
are approached by the other
5 Check the tools and the materials after used
Affective assessment :
Give () according to student attitude
No AspectScore
1 2 31 Presence
2 Team Work
3 Responsibility
4 Help friend who have problem
Rubrics:
1) Score 3 = student come ontimeScore 2 = late < 10 minutes
Score 1 = late > 10 minutes
2) Score 3 = student totally contribute their ability in team workScore 2 = student rarely give contribution in team work
Score 1 = student does not give any contribution in team work
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3) Score 3 = student totally responsible to their task in team workScore 2 = student do their task just if he/she is warned by others members.
Score 1 = student does not responsibles (does not do the task) in team work
4) Score 3 = student totally helps friend who have problemScore 2 = student rarely helps friend who have problem
Score 1 = student does not help friend who have problem
Cognitive assessment
Objective
Question numberscore
1 0
1
2
3
4
5
6
7
8
9
10
Rubric:
Score 1: student choices the right answer
Score 0: student choices the wrong answer
Total score of objective =
x 100
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Essay
Question number score
10 5 3 1
1
2
3
4
5
Rubric:
Score 10: student answers the questions with true process and right final answerScore 5 : student answers the questions with true process but wrong final answer
Score 3 : student answers the questions with wrong process but right final answer
Score 1 : student answer the question with both process and final answers are wrong
Total score of essay = 2 achieved score
Total score of formative test =
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References
Nowikow, Igor and Brian heimbecker . 2001 . Physics Concepts and Connections. Canada :
Irwin Publishing.
Zike, Dinah. 2008.Glencoe Science. USA: McGraw-Hill
Daroji and Haryati . 2010 . The Essentials of Physics . Solo : Tiga Serangkai.
http://en.wikibooks.org
http://en.wikibooks.org/http://en.wikibooks.org/http://en.wikibooks.org/