In stellar nucleosynthesis, the fusion of helium-4 nuclei (24He^4_2\text{He}24He) to form heavier elements requires a core temperature of approximately 108 K10^8\text{ K}108 K, which is significantly higher than the temperature required for hydrogen fusion.
Explain why helium fusion requires such extremely high temperatures, referencing the kinetic energy of the nuclei, their charges, and the forces involved.
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.