Physics A-Level
Critical
What Critical means in Physics A-Level, as defined for OCR.
Definition of Critical
Check what you remember
Read the wording for your board, then hide it and explain Critical in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: OCR
The reactor is kept in this state when on average one neutron per fission causes another fission.
Topics that use Critical
- Nuclear fission and fusion (OCR A-Level)
Related terms
- Alpha and beta decay
- Barium
- Binding energy
- Binding energy per nucleon against nucleon number curve
- Chain reactions
- Characteristic X-rays from shell transitions
- Compton effect
- Computer reconstruction of attenuation data
Using Critical in the exam
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