An experimental sensor plate on a deep-space probe is initially at −150∘C-150^\circ\text{C}−150∘C. It is then exposed to a continuous beam of thermal radiation from a calibration source. The temperature of the plate is recorded at regular intervals as shown in the table below.
| Time in minutes | Temperature in ∘C^\circ\text{C}∘C |
|---|---|
| 0 | -150 |
| 5 | -80 |
| 10 | -30 |
| 15 | 2 |
| 20 | 24 |
| 25 | 39 |
| 30 | 48 |
| 35 | 53 |
| 40 | 55 |
| 45 | 56 |
| 50 | 56 |
Explain, in terms of radiation and energy balance, why the temperature of the sensor plate initially rises and then eventually remains at a constant value of 56∘C56^\circ\text{C}56∘C.
7 exam-style questions on Edexcel GCSE Physics 5.3 Black body radiation (physics only). Each one has a worked solution and a mark scheme showing where the marks go.