Conservation laws
What Conservation laws means in Physics A-Level, as defined for AQA.
Definitions of Conservation laws
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Reference: AQA
Lepton number conservation is used alongside conservation of charge, baryon number and energy to test whether a proposed reaction is allowed.
Charge, lepton number and energy-momentum are conserved in particle interactions such as the decay of a muon into an electron.
Conservation of A and Z must hold on both sides of every decay equation.
Topics that use Conservation laws
- Classification of particles (AQA A-Level)
- Nuclear instability (A-level only) (AQA A-Level)
Related terms
- Alpha emission
- Baryon number
- Baryons
- Baryons and antibaryons
- Beta-minus decay
- Beta-plus decay
- Conservation of baryon number
- Conservation of strangeness
Using Conservation laws in the exam
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