Radiation Therapy Physics

Concepts Review Blog

Sara Lorraine Gill, MSRS, CMD

Medical Dosimetrist and Educator

27. Why are some nuclei stable while others decay?

Sara Lorraine Gill

Published on: 15/10/2026

Learn what makes atomic nuclei stable or unstable. Explore the balance between protons, neutrons, the strong nuclear force, and electrical repulsion, plus the different types of radioactive decay, including alpha, beta, and gamma decay.

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26. Radiation from Atomic Nuclei

Sara Lorraine Gill

Published on: 04/10/2026

Discover how mass defect, binding energy, and Einstein’s equation, E = mc², explain the energy held inside atomic nuclei. Learn why changes in nuclear binding can release energy in fission, fusion, and radioactive processes.

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