A metal block on a satellite has a mass of 0.50 kg.
When the satellite moves out of the Earth's shadow into sunlight, the block absorbs radiation at a power of 60 W. At first, the block emits radiation at a power of 35 W.
Calculate the net energy gained by the block in the first 20 s.
Assume that the powers stay constant during this time.
The specific heat capacity of the metal is 900 J/kg ∘C900\ \text{J/kg}\ ^{\circ}\text{C}900 J/kg ∘C.
Calculate the temperature rise of the block in the first 20 s.
Use the equation
ΔQ=m×c×Δθ\Delta Q = m \times c \times \Delta \thetaΔQ=m×c×Δθ
Explain why the temperature rise of the block in the next 20 s is smaller.
Later, the satellite moves back into the Earth's shadow. The power absorbed by the block falls to 5 W.
Describe and explain what happens to the temperature of the block.
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.