The Joint European Torus (JET) and the upcoming ITER project are experimental tokamak reactors designed to harness energy from nuclear fusion using deuterium (12H^{2}_{1}\text{H}12H) and tritium (13H^{3}_{1}\text{H}13H) as fuel.
Describe the process of nuclear fusion occurring in such a reactor, and explain why exceptionally high temperatures are necessary for this reaction to occur.
94 exam-style questions on Edexcel GCSE Physics 6.5 Uses and dangers of radioactivity. Each one has a worked solution and a mark scheme showing where the marks go.