Late in its life, a star like the Sun begins to run out of hydrogen in its core. The core of the star starts to contract.
Which statement explains why the core contracts?
More energy is released by fusion, so gravity becomes much stronger
The core cools down, so the force of gravity on it becomes smaller
Less energy is released by fusion, so gravity is no longer balanced
The core loses most of its mass, so there is less to hold it together
50 exam-style questions on OCR GCSE Physics 8.3 Beyond Earth, covering 8.3.1 Red-shift and the expanding universe, 8.3.2 Evidence for the Big Bang model, 8.3.3 Formation of the Sun and stellar equilibrium, 8.3.4 Radiation emitted by hot bodies, 8.3.5 The solar system and satellites, 8.3.6 Gravity and circular orbits, 8.3.7 Orbital radius and orbital speed, 8.3.8 Radiation balance and the temperature of the Earth, and 8.3.9 Seismic waves and exploring hidden structures. Each one has a worked solution and a mark scheme showing where the marks go.