The table shows the emitted power of an object at different temperatures. It absorbs a constant power of 50 W and transfers energy only by radiation.
| Temperature in ∘C^\circ\mathrm{C}∘C | Emitted power in W\mathrm{W}W |
|---|---|
| 20 | 30 |
| 30 | 40 |
| 40 | 50 |
| 50 | 62 |
The object starts at 50 ∘C50\,^\circ\mathrm{C}50∘C. Which describes its initial change and final steady temperature?
initial cooling; steady temperature 40 ∘C40\,^\circ\mathrm{C}40∘C
initial warming; steady temperature 40 ∘C40\,^\circ\mathrm{C}40∘C
initial cooling; steady temperature 20 ∘C20\,^\circ\mathrm{C}20∘C
initial warming; steady temperature 20 ∘C20\,^\circ\mathrm{C}20∘C
96 exam-style questions on Edexcel GCSE Physics 5.3 Black body radiation, covering 5.3.1 Emission of radiation and temperature, 5.3.2 Radiation balance and constant temperature, and 5.3.3 The temperature of the Earth. Each one has a worked solution and a mark scheme showing where the marks go.