Physics (AS & A Level) · May / June 2025 · Paper 11 · Question 39

Which statement explains why alpha-particles have discrete energies, but beta-particles have a continuous range of energies?

1. ABeta-particles have a much smaller mass than alpha-particles which means beta-particles can be emitted with a larger range of velocities.
2. BOnly alpha-particles experience repulsion from the nucleus which is dependent on the number of protons in the nucleus.
3. COnly beta-particles are emitted with another lepton and some energy is transferred to the other lepton.
4. DOnly the energy of alpha-particles is discrete because the composition of alpha-particles is always the same.

As printed in the paper