Physics A-Level
Thermal neutrons and moderation
What Thermal neutrons and moderation means in Physics A-Level, as defined for AQA.
Definition of Thermal neutrons and moderation
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Reference: AQA
Fast neutrons must be slowed by a moderator, for example graphite or water, to become thermal neutrons with energies comparable to the thermal motion of surrounding particles, so that further absorption and fission are likely.
Topics that use Thermal neutrons and moderation
- Induced fission (A-level only) (AQA A-Level)
Related terms
- Balance of neutron production and absorption
- Chain reactions
- Control rods
- Coolant
- Induced fission
- Moderator
- Neutron absorption cross-section
- Neutron moderation and chain reactions
Using Thermal neutrons and moderation in the exam
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