Physics A-Level
Alpha decay
What Alpha decay means in Physics A-Level, as defined for AQA, OCR.
Definitions of Alpha decay
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Reference: AQA
Emission of an alpha particle (2 protons and 2 neutrons, a helium nucleus), reducing proton number by 2 and nucleon number by 4.
The parent nucleus loses two protons and two neutrons, emitting a helium nucleus.
Topics that use Alpha decay
- Stable and unstable nuclei (AQA A-Level)
- Radioactivity (OCR A-Level)
Related terms
- Beta-minus decay
- Beta-plus decay
- Absorber
- Binding and saturation of the strong force
- Carbon-14 and half-life
- Conservation of charge
- Conservation of momentum
- Conservation of nucleon number
Using Alpha decay in the exam
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