A student measures infrared emission from two surfaces at the same temperature and distance. The detector gives a background reading of 4 units. The readings are 28 units for surface P and 12 units for surface Q, including background.
After correcting for background, what is the ratio of the readings for P to Q?
7:37:37:3
2:12:12:1
4:14:14:1
3:13:13:1
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.