The rates of emission from four radioactive sources are measured at 30-minute intervals.
Each row in the table shows the results for one of the radioactive sources.
| Source | Rate of emission at t=0t = 0t=0 (counts/s) | Rate of emission at t=30 mint = 30\text{ min}t=30 min (counts/s) | Rate of emission at t=60 mint = 60\text{ min}t=60 min (counts/s) |
|---|---|---|---|
| A | 800 | 400 | 200 |
| B | 800 | 200 | 50 |
| C | 400 | 380 | 361 |
| D | 400 | 280 | 200 |
Which source has the shortest half-life?
Source A
Source B
Source C
Source D
144 exam-style questions on CIE IGCSE Physics 5.2.4a Half-life. Each one has a worked solution and a mark scheme showing where the marks go.