Physics (AS & A Level) · May / June 2025 · Paper 14 · Question 38

A nucleus W of a radioactive isotope emits a β– particle and forms nucleus X. Nucleus X emits an α-particle to form nucleus Y. Nucleus Y emits a β– particle to form nucleus Z. Which statement about Z is correct?

1. AZ is a nucleus of a different element from W and has a higher nucleon number.
2. BZ is a nucleus of a different element from W and has a lower nucleon number.
3. CZ is a nucleus of the same element as W and has a higher nucleon number.
4. DZ is a nucleus of the same element as W and has a lower nucleon number.

As printed in the paper