General Laboratory Practice

Spend some time reading the relevant manual the day before you attend the laboratory. The purpose of this preparation is to allow you to do some planning, and to enable you to keep the whole of the experiment in mind while you are performing the various parts.

Safety in labs

You will be given a general leaflet on this subject issued by the University for the guidance of all departments. There will be a copy available for reference in the laboratory. Read it and apply it to your own work. In the Course 1 laboratory there are some special hazards associated with X-rays, lasers and high voltages. Be aware of these hazards - although your experiment may not involve any of them a neighbouring one might.

Smoking is absolutely forbidden in the course 1 laboratory as it is in all parts of the School of Physics. Food and drink are not permitted in the laboratory.

Care of apparatus

The equipment you use in the laboratory is expensive. On average, each experimental set-up costs £4000. A very important experimental skill is handling equipment with appropriate sensitivity. Electrical and optical equipment are particularly at risk. If you meet a piece of equipment which is unfamiliar to you, ask about its use. You will also need to learn how to read and interpret manufacturer's instruction manuals.

Most electrical measuring equipment can be damaged by misuse. The cost of repair of a simple meter is often close to the cost of a new one. Please take great care with the equipment being used. Think carefully before connecting power to electrical circuits. If in doubt about the correctness of your circuits, ask.

Take great care with optical equipment. Never touch diffraction gratings, lenses or mirrors with your fingers and never attempt to clean a front-silvered mirror.

Accidents do, however, happen. So, if in spite of all reasonable precautions you do damage something, please notify a demonstrator promptly so that arrangements can be made for repairs.

End of a laboratory session

Disconnect your apparatus when the experiment is finished, or at the end of the working day. This is particularly important during projects. Please leave the work environment in a tidy state, in particular leave your bench exactly how you found it - put away all leads, etc. that were fetched from the laboratory trolley.

What to do if you miss a laboratory session

Although attendance for laboratory sessions is mandatory, you may be absent from the laboratory class for a genuine reason, e.g. illness. When you return, a self-certification form (available from outside the laboratory) should be sent to the Senior Tutor. It may be possible to catch up on work missed later in the year. This is not an automatic option but will be subject to review by the Head of Year.

Assessment

The laboratory work forms part of one module for each semester and a minimum standard needs to be achieved to allow progression to the second year.

Marks for the lab report (15%) are combined with the continuous assessment marks (85%). Marks are awarded for each experiment. The meanings of the range of marks are:

9 - 10
Very impressive work, showing original thought.
71/2 - 81/2
Outstanding work, more done than expected.
7 - 71/2
Good work, everything completed and correct.
51/2 - 61/2
Competent work, with a few mistakes or omissions.
4 - 5
Satisfactory work, but with a major mistake or omission.
3 - 31/2
Not good enough, with many mistakes and omissions.
0 - 21/2
Not good enough, with many mistakes and omissions.

The kinds of things looked for in lab work are:

  • Evidence of planning and forethought in carrying out the experiment.
  • Good record keeping.
  • Sensible experimental technique.
  • Good results, including estimates of the accuracy and precision.
  • Appreciation of the limitations of the experiment.
  • An understanding of the physics.

Your laboratory notebook should provide the following information for each experiment:

  • Title of the experiment.
  • The date the experiment was started.
  • A brief description of the experimental routine.
  • All experimental observations and errors.
  • Tables of principal results.
  • Important graphs.
  • A brief conclusion.