A student measured the intensity of infrared radiation emitted by a sheet of window glass at different surface temperatures.
| Surface temperature in °C | Intensity in W/m² |
|---|---|
| 40 | 490 |
| 60 | 630 |
| 80 | 560 |
| 100 | 990 |
The student checked the result at 80 °C by repeating the measurement. The repeated intensity was 790 W/m².
What should the student conclude about the two results at 80 °C?
Treat 560 W/m² as anomalous because 790 W/m² is consistent with the temperature trend.
Use the mean of 560 W/m² and 790 W/m² because both were measured at 80 °C.
Treat 630 W/m² as anomalous because it is higher than the first result at 80 °C.
Treat 790 W/m² as anomalous because it does not match the first result at 80 °C.
106 exam-style questions on AQA GCSE Physics 6.3 Black body radiation, covering 6.3.1 Emission and absorption of infrared radiation and 6.3.2 Perfect black bodies and radiation. Each one has a worked solution and a mark scheme showing where the marks go.