Guide to writing a partial Lab Report in

Guide to writing a partial Lab Report in physics Aim: Estimation of wavelength of light using a diffraction grating.

DSE Physics Lab report (Spectrum by diffraction grating)

The procedures in an experiment • A Lab manual tells you what to do as clearly as possible so it uses language like: • Place a ray box. • Set a metre rule M 1.

We will start with the procedures in the Lab menu 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

Highlight the actions and what receives the action 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil. Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

Highlight the actions and what receives the action 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil. Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

Highlight the actions and what receives the action 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil. Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

Highlight the manner or time or space of the action 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil. Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

Highlight the manner or time or space of the action 1. 2. 3. 4. 5. 6. 7. Place a ray box at 2 m from a diffraction grating and place the filament of the light bulb vertically. Locate the diffraction grating at the end of the metre rule M 2. Place the other end of the metre rule M 2 to the centre of the metre rule M 1. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. View the light through the diffraction grating. Observe the vertical diffraction pattern. Locate the middle of the 1 st order diffracted red light along the metre rule M 1 with a pencil. Measure the distance x between the pencil and the centre of the central white light. Record the distance x in Table B 9. 1 Repeat steps 5 and 6 for measuring the middle of the 2 nd order diffracted red light.

The writing language in a Lab Report • A Lab Report tells us what we did, so the writer could say, eg: • I placed a ray box. • I set a metre rule. • However, we want to focus on what we did, but not who did it, we put “the things that received the actions“ at the front and we move who or what did the action to the back or hide it completely. eg: • A ray box was placed (by me). (the ray box received the action – we call it the ‘done to’. ) • A metre rule was set (by me). (the metre rule receicved the action – it is the done to)

Constructing the passive voice — Example 1 Instruction Place the light bulb vertically. placed the light bulb vertically. Active voice This says what we did. We Passive voice This says what was done. The light bulb was placed vertically.

Constructing the passive voice — Example 2 Place Instruction a ray box about 2 m from a diffraction grating. Active voice This says what we did. We Place Passive voice This says what was done. a ray box was placed about 2 m from a diffraction grating.

Constructing the passive voice — Example 3 Instruction Set a metre rule M 2 perpendicular to the diffraction grating. Active voice This says what we did. We set a metre rule M 2 perpendicular to the diffraction grating. Passive voice This says what was done. A metre rule M 2 was set perpendicular to the diffraction grating.

Writing the method stage in a Lab Report – Activity 1 Write what was done in these steps of the experiment — write in the past tense and in the passive voice. 2. (a) Locate the diffraction grating at the end of the metre rule M 2. Ans: The diffraction grating was located at the end of the metre rule M 2. (b) Place another metre rule M 2 from the diffraction grating to the centre of the metre rule M 1. Ans: Another metre rule M 2 was placed from the diffraction grating to the centre of the metre rule M 1. (c) Ans: 3. Set the perpendicular distance between the diffraction grating and the metre rule M 1 to L = 1 m. The perpendicular distance between the diffraction grating and the metre rule M 1 was set to L=1 m. Set a metre rule M 1 with its 50 cm mark at the midway across the line joining the ray box and the diffraction grating. Ans: A metre rule M 1 with its 50 cm mark was set at the midway across the line joining the ray box and the diffraction grating.

Writing the method stage in a Lab Report – Activity 1 (continued) Write the remaining steps of the experiment, telling us what was done. Answers 4. The light was viewed through the diffraction grating. The vertical diffraction pattern was observed. 5. The middle of the 1 st order diffracted red light along the metre rule M 1 was located with a pencil. 6. The distance x was measured between the pencil and the centre of the central white light. The distance x was recorded in Table B 9. 1. 7. Steps 5 and 6 were repeated for measuring the middle of the 2 nd order diffracted red light.

Revisions 1. Highlight the “action” in green. 2. Highlight the “things we did” in red. 3. Highlight the “where we did” in blue. 4. Re-arranged them in passive voice. You did it. Good!