A radioactive source is placed 30 mm in front of a detector.
The count rate from the source is 1500 counts/minute1500\text{ counts/minute}1500 counts/minute.
With a thin sheet of paper between the source and the detector, the count rate is 900 counts/minute900\text{ counts/minute}900 counts/minute.
With the paper removed and a sheet of aluminium 5 mm thick placed between the source and the detector, the count rate is 0 counts/minute0\text{ counts/minute}0 counts/minute.
Which radioactive emissions are coming from the source?
alpha and beta only
alpha and gamma only
beta and gamma only
alpha, beta, and gamma
134 exam-style questions on CIE IGCSE Physics 5.2.2a Alpha, beta and gamma emission. Each one has a worked solution and a mark scheme showing where the marks go.