Stable and unstable nucleiAQA A-Level Physics: Mind map

Exam questions on Stable and unstable nuclei

1. A physics class is discussing why a nucleus, which contains positively charged protons packed very close together, does not fly apart.
   Explain why it is important that the strong nuclear force becomes repulsive at very small separations.2 marks
2. Radium-226, $^{226}_{88}\mathrm{Ra}$, is an unstable nucleus that decays by emitting an alpha particle to form an isotope of radon (Rn).
   Write the nuclear equation for the alpha decay of radium-226.2 marks
3. Strontium-90, $^{90}_{38}\mathrm{Sr}$, is a waste product of nuclear fission. It decays by beta-minus emission to yttrium (Y). When beta decay was first studied, the electrons emitted by a sample of a single beta-minus emitter were found to have a continuous range of kinetic energies up to a well-defined maximum, rather than all having the same energy.
   Write a nuclear equation for the beta-minus decay of strontium-90.3 marks