LuduminaWA-11 · WA-U3 · Planned
Infrared surfaces investigation
Learning objectives
Plan comparisons of absorption/emission for different surfaces; control geometry and temperature.
8463 §§4.6.2.2;8.2.10 / 8464 §§6.6.2.2;10.2.21
DfE single-science pp.37–39 / Combined pp.32–33. Evidence checked 30 September–1 October 2026. Skills: WS2.1–2.7,3.4,3.7; MS2b,2c,4c.
Explanation
A surface comparison needs equal geometry, distance and relevant starting temperatures. Good infrared absorbers are also good emitters. Compare like measurements and state whether the detector measures radiation directly or whether temperature change provides indirect evidence.
Concepts, equations and units: Infrared transfer; temperature °C, time s, detector signal in labelled units; dark matt versus light shiny surfaces; no Stefan–Boltzmann equation.
Prediction, demonstration and game exercise
Predict, observe, explain
Compare model detector readings from equally hot surfaces and warming rates under equal irradiation.
Planned learner game exercise
Select detector distance, initial temperature, surface finish and repeats; collect both absorption/emission evidence.
Independent practice
Plot results with uncertainty; distinguish temperature readings from direct radiation measurements.
Original practice example · Shared
Equally hot surfaces at the same distance give repeated detector signals: matt A = 18, 19, 20; shiny B = 6, 7, 8 arbitrary units. Compare means.
Show working and model answer
Working / reasoning
Mean A = 57/3 = 19; mean B = 21/3 = 7. A’s emitted detector signal is larger under the stated controls.
Answer
19 and 7 units; A emits a larger measured IR signal in this setup.
Exit check and success criteria
Controlled comparison with labelled data and a conclusion limited to the tested surfaces.
During practice, compare the prediction with evidence and give an error-specific prompt. The exit item uses a fresh context or fresh values, answered independently.
Misconceptions, practical links and mastery
Check these misconceptions
Black surfaces only absorb and never emit; visible colour alone determines every radiation property.
Practical preparation
RP-P10/RP-C21; AT1,4.
Virtual preparation and revision only. Required hands-on activities and school records remain separate.
Proposed mastery
0: not yet evidenced. 1: supported. 2: independent exit criteria met. 3: successful changed-context transfer. Advance at 2; revisit with fresh retrieval. These are not GCSE grades.