A body transfers energy only by radiation and has no overall change in internal energy during 60 s. It absorbs 3.0 kJ in this time. During the first 20 s, its average emitted power is 30 W.
What is its average emitted power during the remaining 40 s?
40 W40\,\mathrm{W}40W
50 W50\,\mathrm{W}50W
60 W60\,\mathrm{W}60W
75 W75\,\mathrm{W}75W
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.