The rate of nuclear fusion in a star's core increases. The radius of the star then begins to increase.
Which statement explains this?
The outward push becomes greater than the inward pull of gravity.
The outward push becomes weaker than the inward pull of gravity.
The inward and outward effects both become weaker by equal amounts.
The inward pull of gravity becomes greater as the core gets hotter.
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.