Two electrically heated metal food-warming plates are identical apart from the finish on their undersides. Each plate is kept at 80 ∘C80\ ^\circ\text{C}80 ∘C. An infrared detector is placed in the same position beneath each plate.
| Finish on underside | Infrared intensity at the detector in W/m2\text{W/m}^2W/m2 |
|---|---|
| matt black | 14 |
| shiny silver | 3 |
Give the finish of the underside that emits infrared radiation at the greater rate.
Explain how the detector measurements support your answer to part (a).
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.