Nuclear stability
What Nuclear stability means in Physics A-Level, as defined for AQA, OCR.
Definitions of Nuclear stability
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Reference: OCR
The short-range attraction explains why large nuclei need more neutrons for stability, because the strong force only acts between neighbouring nucleons while electrostatic repulsion acts throughout the nucleus.
A higher value of average binding energy per nucleon means a more stable nucleus, because more energy must be supplied per nucleon to separate it.
Kept by the strong nuclear force acting between nucleons, which counteracts the electrostatic repulsion between protons and binds the nucleus.
Nuclei near the peak of the curve are the most stable, with the highest binding energy per nucleon.
Topics that use Nuclear stability
- Mass and energy (A-level only) (AQA A-Level)
- Stable and unstable nuclei (AQA A-Level)
- Nuclear fission and fusion (OCR A-Level)
- The nuclear atom (OCR A-Level)
Related terms
- Binding energy
- Conservation of charge
- Conservation of nucleon number
- Energy release in nuclear reactions
- Mass defect
- Alpha and beta decay
- Alpha decay
- Atomic and nuclear density
Using Nuclear stability in the exam
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