Physics GCSE
chain reaction
What chain reaction means in Physics GCSE, as defined for AQA, OCR.
Definitions of chain reaction
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Reference: AQA
A self-sustaining sequence in which at least one neutron from a fission is absorbed by another large nucleus, causing a further fission that releases more neutrons again.
Released neutrons can be absorbed by other unstable nuclei, causing them to split in turn, so further fissions become possible.
Released neutrons can be absorbed by other large nuclei, sustaining this process.
Topics that use chain reaction
- Nuclear fission (AQA GCSE)
- Uses and hazards (OCR GCSE)
Related terms
- neutron absorption
- nuclear fission
- contamination
- control rods
- energy released per fission
- energy transfer to thermal store
- fissions per second
- Half-life
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