Deep within the core of a main-sequence star, hydrogen nuclei undergo thermonuclear fusion to form helium.
State one extreme physical condition that must exist within the stellar core to enable these positive nuclei to overcome their mutual electrostatic repulsion and undergo fusion.
94 exam-style questions on Edexcel GCSE Physics 6.5 Uses and dangers of radioactivity, covering 6.5.1 Uses of radioactivity, 6.5.2 Dangers of ionising radiation and precautions, 6.5.3 Half-life and radiation dangers, 6.5.4 Safety precautions for radiation exposure, and 6.5.5 Contamination and irradiation. Each one has a worked solution and a mark scheme showing where the marks go.