A blank nine-step write-up with the correct table headings. Print it for a real lesson and fill it in by hand. See the specimen lab book
Blank write-up: Infrared radiation
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Study Hack Lab
RP 10 · Physics
Infrared radiation
Write-up template
Name
Date
Course
GCSE Physics
Board and specification
AQA GCSE Physics (8463), 4.6.2.2AQA GCSE Combined Science: Trilogy (8464), 6.6.2.2Apparatus and techniques: AT 1, AT 4
Class and teacher
Aim
Investigate how the amount of infrared radiation a surface emits depends on the nature of the surface: with a Leslie cube, then with three flasks cooling.
Contents
Plan and risk assessment
Apparatus
Method
Results
Graph
Analysis
Conclusion and evaluation
Make safe and clear up
A blank write-up for use in a real lesson. The headings follow the AQA required practical; the readings are yours to take. Layout v1, practical v2. Original material; not affiliated with AQA, which has not reviewed it.
1 Plan and risk assessment
Every object emits infrared radiation, and hotter objects emit more. At the same temperature, a matt black surface emits the most and a shiny silver (polished metal) surface the least. Matt white paint is nearly as good an emitter as matt black: in the infrared it is the shininess that matters, not the colour.
A good emitter is a good absorber
Variables
Independent (you change)
Dependent (you measure)
Control (you keep the same)
Prediction
All four faces of the cube are at the same temperature. Which face will emit the most infrared?
Which face will emit the least infrared?
How will the matt white face compare with the matt black face?
Risk assessment
Hazard
Harm it could cause
Control
2 Apparatus
Leslie cube with lid Four faces at the same temperature: matt black, shiny black, matt white and shiny silver.
Kettle Very hot water for the cube and the flasks.
Heatproof mat Under the cube and the flasks.
Infrared detector (resolution 0.1 °C or 0.01 mV) An infrared thermometer, or an infrared detector with a meter: measures the infrared from each face.
Ruler and clamp (resolution 1 mm) Keep the detector 5 cm from each face.
Four thermometers (resolution 1 °C divisions, read to 0.5 °C) The water in the cube and in each flask.
Three flasks with lids Painted matt black, painted matt white, and wrapped in shiny aluminium foil.
250 ml measuring cylinder (resolution 2 ml) The same volume of water in each flask.
Stopwatch (resolution 0.01 s) Times the flasks’ cooling.
3 Method
Write numbered steps someone else could follow. Say what you measure, with which instrument, and how you keep it a fair test.
4 Results
The table is drawn before you measure. Record each reading to the resolution of the instrument, then work out the mean of your repeats, leaving out any anomaly.
The Leslie cube · Infrared thermometer 5 cm from each face.
Surface
Reading 1 in °C
Reading 2 in °C
Reading 3 in °C
Mean temperature in °C
Matt black
Shiny black
Matt white
Shiny silver
The water in the cube
When
Temperature of the water in °C
Start
End
The three flasks · 200 ml of hot water in each flask.
Time in minutes
Temperature of the matt black flask in °C
Matt white in °C
Shiny silver in °C
0
2
4
6
8
10
Fall in 10 minutes
Anomalies
Ring any anomalous result. Say what probably went wrong and whether you repeated it.
5 Graph
Cooling curve for the matt black flask · Choose your axes: the independent variable goes on the x-axis. Label each axis with the quantity and unit.
6 Analysis
Mean for matt black
mean = sum of the values ÷ number of values
Answer
Matt black compared with shiny silver
difference = mean (matt black) − mean (shiny silver)
Answer
How much the matt black flask cooled
fall in temperature = starting temperature − final temperature
Answer
7 Conclusion and evaluation
Conclusion
Conclusion: what do your results show? Use your own numbers.
Sources of error
For each, say whether it is systematic or random, and how it affected your results.
The distance from the detector to each face, judged by eye
The water cooling while the faces are measured
Readings taken before the display settled
The student’s own infrared reflected by the shiny face
Fingerprints on the shiny face
The detector pointing at an angle to the face
Flasks started at different temperatures
Different volumes of water in the flasks
Improvement
How could you improve the method? Say why it would help.
8 Make safe and clear up
Switch off and unplug the kettle; leave the cube and flasks to cool on the mat
When cool, empty the cube and the flasks into the sink with the lids off
Dry the cube and wipe the shiny face so it is ready for the next class
Switch off the detector and put the thermometers back in their case