Physics · May / June 2025 · Paper 11 · Question 36

A radioactive nucleus X decays to another radioactive nucleus. After a number of decays, a stable nucleus Q is produced. The proton number (atomic number) of X is equal to that of Q. The nucleon number (mass number) of X is four more than that of Q. Which radiations are emitted to produce Q?

1. Atwo alpha-particles
2. Bone alpha-particle and one beta-particle
3. Ctwo alpha-particles and one beta-particle
4. Done alpha-particle and two beta-particles

As printed in the paper