Lab Report Structure

1. Aim & objectives of the experiment

Explain the aim & objectives of the experiment.

2. Introduction

Mention the experiment.

Explain the principle of the experiment.

3. Equipment used

List the equipment you used.

4. Safety

Did you consider any safety issues while carrying out the

experiment? Explain.

5. Method

Provide any ray diagrams or diagrams that you used.

Explain the formula and terms used with appropriate units.

Explain the procedure.

6. Results

Include the tables.

Attach the relevant graphs.

Show the working for each type of calculation.

7. Uncertainties

Explain the uncertainty involved in the experiment.

Error analysis should be provided here.

8. Discussion

Discuss your result

Relate your findings to the theory.

What result did you expect? What did you get? If you got

unexpected result what went wrong? How it could have been

rectified.

9. Conclusion

Give your conclusions.

10.References & Bibliography

List the references you used (books, websites etc.). Harvard

referencing should be used. Don’t forget the citation. Also, include

all the other sources consulted, even if not directly cited in the

report.

Note:

Read your report and use spell check.

Do not cut and paste from websites.

Don’t forget to provide references

About this experiment：

Experiment 1: Diffraction Grating.

Caution. Follow the specific instructions you are given about working safely with laser

light.

You are provided with a laser light source, and two diffraction gratings. One grating has

known line spacing. Task 1 is to use the grating with the known spacing to determine

the wavelength of the laser light. Task 2 is to work out the spacing on the unknown

grating, using the value of λ found in task 1.

For a diffraction grating nλ = dsinθn

where n is the order of the maximum,

λ is the wavelength,

d is the slit spacing of the grating and

θn is the angle between the direction of the central beam and the direction of the

nth maximum.

Task 1

1. Set up the apparatus to produce an interference pattern on the screen.

2. Draw a labelled sketch of your experiment.

3. Indicate, by labels or explanation, how you will obtain n, d, and θn for each

maximum you investigate

4. List the measurements required.

5. Draw a suitable table for your results.

Include quantities, units and uncertainties in the table headings.

6. Take measurements and record them in the table

7. Plot a suitable graph and use the gradient to find λ.

To find the wavelength of the light

n X (unit) tanθ = x/y θ(unit) sinθ

1 1.4cm 0.035 2.004 0.035

2 2.6cm 0.065 3.719 0.065

3 3.9cm 0.097 5.540 0.096

4 5.2cm 0.13 7.407 0.129

5 6.5cm 0.16 9.090 0.158

8

n is the order

y is the distance between the grating and screen

x is the distance between the central maximum and nth maximum

λ = d sinθ /n

{sinθ/n is obtained from the graph}