A radioactive source has a half-life of 8 days8\text{ days}8 days.
A detector near the source shows a reading of 4800 counts per second4800\text{ counts per second}4800 counts per second.
Background radiation can be ignored.
What is the reading on the detector 24 days24\text{ days}24 days later?
600 counts per second600\text{ counts per second}600 counts per second
1200 counts per second1200\text{ counts per second}1200 counts per second
1600 counts per second1600\text{ counts per second}1600 counts per second
2400 counts per second2400\text{ counts per second}2400 counts per second
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.