In a nuclear reactor, each fission of a uranium-235 nucleus releases two or three neutrons.
Which statement describes how a chain reaction happens?
The neutrons are absorbed by other uranium-235 nuclei, which then split
The neutrons are absorbed by the reactor walls, which then split apart
The neutrons join together to form new uranium-235 nuclei, which split
The neutrons decay into protons, which then cause more nuclei to split
48 exam-style questions on OCR GCSE Physics 6.2 Uses and hazards, covering 6.2.1 Contamination and irradiation, 6.2.2 Half-life and radiation hazards, 6.2.3 Medical uses of nuclear radiation, 6.2.4 Nuclear fission and chain reactions, and 6.2.5 Nuclear fusion. Each one has a worked solution and a mark scheme showing where the marks go.