What this tests
Syllabus point 5.2 — Radioactivity, in Nuclear physics. Difficulty hard (estimated from the question's demands, not a Cambridge rating).
Also set in
The same question, as Cambridge printed it in other papers.
Cambridge IGCSE Physics 0625 · 5.2 Radioactivity
November 2010 · Paper 12 · Question 40
One real Cambridge question from Nuclear physics, with the official answer. Cambridge has printed this question 3 times.