A main sequence star remains approximately the same size for a long time. Which statement explains this?
Gravity stops acting while hydrogen fusion continues.
Thermal expansion stops while hydrogen fusion continues.
Gravity and thermal expansion both act towards the centre.
Gravity and thermal expansion have balancing effects.
75 exam-style questions on Edexcel GCSE Physics 7.3 Stars, covering 7.3.1 Evolution of stars similar to the Sun, 7.3.2 Evolution of massive stars, and 7.3.3 Observing the Universe. Each one has a worked solution and a mark scheme showing where the marks go.