The Earth's average temperature has been constant for many years. Strong winds spread pale sand across a very large area of dark rock. Assume the only direct effect of the sand is to change the amount of incoming solar radiation reflected. Which statement describes what initially happens?
The Earth absorbs radiation faster than it emits radiation, so its average temperature starts to rise.
The Earth continues to absorb and emit radiation at equal rates, so its average temperature stays constant.
The Earth absorbs radiation more slowly than it emits radiation, so its average temperature starts to rise.
The Earth absorbs radiation more slowly than it emits radiation, so its average temperature starts to fall.
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.