A sample of nuclide X X\,X containing 3N nuclei has an activity of 2A. The half-life of X X\,X is 18 hours18\text{ hours}18 hours.
Another sample of nuclide Y Y\,Y containing 5N nuclei has an activity of 6A.
What is the half-life of nuclide YYY?
3.6 hours3.6\text{ hours}3.6 hours
6.0 hours6.0\text{ hours}6.0 hours
10 hours10\text{ hours}10 hours
90 hours90\text{ hours}90 hours
128 exam-style questions on AQA A Level Physics Radioactivity (A-level only), covering Rutherford scattering (A-level only), $\alpha$ , $\beta$ and $\gamma$ radiation (A-level only), Radioactive decay (A-level only), Nuclear instability (A-level only), Nuclear radius (A-level only), Mass and energy (A-level only), Induced fission (A-level only), and Safety aspects (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.