INTRODUCTION AND LOGISTICS OF THE LABORATORY

INTRODUCTION AND LOGISTICS OF THE LABORATORY

Aim of the labThe aim of the laboratory is to improve skills and experiences to the graduate, so as to be able and capable of carrying out various laboratory analysis and practical work of handling sciences subject with confidence and reliable manner.

It aims to produce general laboratory techniques, in management, and communication in English. Also to enhance understanding of how scientific knowledge actually progressesIt is hoped that this course will give you a taste of the difficulties and thrills of real experimentation; and that you come away with a greater appreciation of how the laws of nature are teased out of real world measurements.

Objectives of the labTo provide familiarity and build confidence with a range of apparatus. To provide training in how to perform experiments and teach you the techniques of scientific measurement.

To give you practice in recording your observations and communicating your findings to others.To demonstrate theoretical ideas in physics, which you will encounter in your lecture courses.

RECORDING EXPERIMENTS IN YOUR LAB. BOOK / DIARY

RECORD is a practice of keeping details of the experimental set up and analysis of results related back to the underlying physics. It is a record of your observations, measurements and understanding of the experiment.

It is not a neat essay containing the background theory or paragraphs copied from other sources, but a real-time account of your experimental method and findings.

The aim of keeping a record work in a manner clear enough is that you or a colleague could understand and attempt to repeat the experiment.When assessing your laboratory write-up, the demonstrator is interested in your measurements, observations, results and conclusions.

You should present a set of measurements and results taken and recorded in such a way that you can understand easily what each number means, what results you have derived, and what conclusions you have drawn.

You should also make notes of any difficulties experienced and sources of uncertainty or error. Ideally the record should be such that you could yourself reconstruct the course of the experiment later - perhaps 20 years later without difficulty.

The measurements presented should be those taken during the performance of the experiment they should not be rewritten before presentation.

A sketch of the apparatus/parts of the apparatus, labeled to correspond with the measurements, serves as a very useful reminder of the experimental arrangement Record units and remember that a statement of precision is an essential part of every measurement. A typical complete observation is l = 8.69 0.01 mm. Whenever possible, plot graphs as the measurements are made. Label the axes of graphs. Choose scales for the axes which make plotting easy

Axes do not have to start at the origin; zoom in sensibly to best display the results. Present the results with a statement of precision and units. Quote the generally accepted value of the quantity you have measured

Try to account for any difference that you see. (Error analysis)( remember to note down where you got this accepted value from).

Comment briefly on the experiment and results.Note however this is not the same as self appraisal. I think the experiment went really well is subjective, unscientific and meaningless

WRITING UP FULL REPORTS OF EXPERIMENTS

An example of a full report and further advice are given in to help you. Very importantly, Your report must be original and not a copy of any part of the notesIt should be a report of what you did; not of what you would like to have done or of what you think you should have done.

That said, credit will be given for discussions on how one might extend and improve an experiment, and what might be done if the experiment were to be repeated

in writing scientific papers omit all details of calculations. Give the report a sensible structure; write in proper, concise English; Use the past tense passive voice,Refer to the given formatfor example "... The potentiometer was balanced ...". The following structure is suggested. It is not mandatory, but you are strongly recommended to adopt it.

Your report should include:1) Abstract". An abstract is a very brief (~50-100 words) synopsis of the experiment performed.

An example is: "The speed of sound in a gas has been measured using the standing wave cavity method for one gas (air) for a range of temperatures near room temperature and for gases of different molecular weights (air, argon, carbon dioxide) at room temperature. The speed in air near room temperature was found to be proportional to T, where T is the gas temperature in Kelvin, and the ratio Cp/Cv for air, argon and carbon dioxide at room temperature was found to be 1.402 0.003, 1.668 0.003 and 1.300 0.003 respectively".

2) Follow the abstract, on a separate page, with an introduction to the experiment. Head this section Introduction.and or theory Here, you should state the purpose of the experiment, and outline the principles upon which it was based. This section is often the most difficult to write.

Remember that the reader will, in general, not be as familiar with the subject matter as the author. Start with a brief general survey of the particular area of physics under investigation before plunging into details of the work performed.

Important formulae and equations to be used later in the report can often, with advantage, be mentioned in the introduction/theory as, by showing what quantities are to be measured, their presence helps in the understanding of the experiment.

Formulae or equations should only be quoted at this stage. Derivations of formulae or equations should be given either by references to sources, for example text books, or in full in appendices. References should be given in the way described below.3) Follow this with a description of the experimental procedure. Head this Experimental Procedure. Write the experimental procedure as concisely as possible: give only the essentials, but do mention any difficulties you experienced and how they were overcome..

All diagrams, graphs or figures should be labeled as figures. Give each a consecutive number (as in Figure 1 etc.), a brief title and, where possible, a brief caption. Give each group or table of measurements a number (as in Table 1 etc.) and a brief title, and use the numbers for reference from the text e.g. the data in Figure 1 exhibits a straight . . .

4) Follow this section with the results of the experiment, discussion of them and comments. Head this Results and discussion. The result of the experiment can be stated quite briefly as "The value of X obtained was N + s (N) UNITS

. For example "The viscosity of water at 20C was found to be (1.02 0.01) x 10-3 Nm-2SDiscussion of the result, or measurements, method etc., can be cross-referenced by quoting the figure, table or report section numbers.

5) Follow this section with your conclusions. Head this Conclusions. The conclusions should restate, concisely, what you have achieved including the results and associated uncertainties. Point the way forward for how you believe the experiment could be improved

6) Follow this section with references. Head this References or Bibliography.There are two main styles used (along with many subtle variations) to detail references. The Harvard method, the name of the first author along with the year of publication is inserted in the text, with full details given, in alphabetical order, at the end of the document.The second style, favored here is known as the Vancouver approach, is slightly different. At the point in your report at which you wish to make the reference, insert a number in square Brackets

e.g. [1]. Numbers should start with [1] and be in the order in which they appear in the report. References should be given in the reference or bibliography section, and should be listed in the order in which they appear in the report. Where referencing a book, give the author list, title, publisher, place published, year and if relevant, page number eg. [1] H.D. Young, R.A. Freedman, University Physics, Pearson, San Francisco, 2004.In the case of a journal paper, give the author list, title of article, journal title, vol no.,page no.s, year.

e.g. [2] M.S. Bigelow, N.N. Lepeshkin & R.W. Boyd, Ultra-slow and superluminal light propagation in solids at room temperature, Journal of Physics: Condensed Matter, 16, pp.1321-1340, 2004.

In the case of a webpage (note: use webpages carefully as information is sometimes incorrect), give title, institution responsible, web address, and very importantly the date on which the website was accessed eg. [3] How Hearing Works, HowStuffWorks inc.,http://science.howstuffworks.com/hearing.htm, accessed 13thJuly 2008

The report format is:

SAFETY IN THE LABORATORY

Maintaining a safe working environment in the laboratory is paramountThe 1974 Health and Safety at Work Act places, applies to students and teachers in university laboratories. The following points supplement contained in "School of Physics Safety Regulations;

1. It is your responsibility to ensure that at all times you work in such a way as to ensure your own safety and that of other persons in the laboratory.2. The treatment of serious injuries must take precedence over all other action including the containment or cleaning up of radioactive contamination.

3. None of the experiments in the laboratory is dangerous provided that normal practices are followed. However, particular care should be exercised in those experiments involving cryogenic fluids, lasers, gases and radioactive materials. Relevant safety information will be found in the scripts for these experiments.

4. All accidents must be reported to a laboratory supervisor or technician who will take the necessary action.5. After an accident a report form, which can be obtained from the technician, must be completed and given to the laboratory supervisor.6. Please alert your Laboratory Supervisor of any medical condition (for e.g. having a pacemaker) which may affect your ability to perform certain experiments.

CHECKLIST

Read through the notes on the experiment that you will be doing BEFORE coming to the practical class. You will be expected to have read all the introductory notes and refreshed yourself of any knowledge of the subject taught in school Read carefully through any additional sections that might be useful eg. use of electronic equipment, statistics.etc Think about the safety considerations that there might be associated with the practical, having read through the lab notes.

On turning up to the lab, listen carefully to any briefing that is given by your demonstrator: he/she will give you tips on how to do the experiment as well as detailing any safety considerations relevant to your experiment.

Read through your experiment before handing it in, checking that you have included errors/error calculations, that you are quoting numbers to the correct number of significant figures and that you have included units. Staple/attach any loose paper (eg. graphs, computer print-outs, questionnaires etc.) into your lab report.

Registration. Attendance will be recorded. Students are expected to sign in/out of the lab Get yourself happy with what is expected of you so you can plan your experiment, which will save you time on the day.

Also you must think about the safety considerations that are required for your experimental work and write a risk assessment, which will be signed off prior to commencing any practical work.

ASSESSMENT OF PRACTICAL WORK

The responsibility for handing your work in at the correct time is yours, and failure to do so will usually mean that a mark of zero will be recorded.

Exceptions to this rule will normally be made only for illness, for which you have notified the School or for circumstance the relevant form has been submitted.

Your experiment should be in a formal report. written in Ms word or sheets of paper(hands) that are either bound or Stapled in only one side page Marked reports may be returned to you, with feedback.

ATTENDANCE

Attendance is compulsory; absence requires a self certificate or medical certificate.Thank you for your attentionContact;Email : hkombo@live.com+255773986832lab supervisor