In a laboratory's secure cupboard are two unlabelled radioactive sources. A scientist knows that one is a beta-emitter and the other is a gamma-emitter, but is not sure which is which.
A radiation detector, a magnet, and a thin sheet of aluminium are available.
Briefly describe two different experimental tests, using this equipment, which would allow the scientist to identify which is the beta-emitter and which is the gamma-emitter.
Test 1:
Test 2:
Radioactive phosphorus-32 (1532P^{32}_{15}\text{P}1532P) decays by emitting β\betaβ-particles.
What are the values of the proton and nucleon numbers of phosphorus-32?
Phosphorus-32 is used in medical treatments. It decays with a half-life of 14 days.
A freshly prepared sample of phosphorus-32 has an activity of 128 units, but after being stored in a clinic, its activity is found to be 8 units.
Determine the time, in days, for which this sample has been stored.
484 exam-style questions on CIE IGCSE Physics 5.2 Radioactivity, covering 5.2.1 Background radiation and measuring count rate, 5.2.2a Alpha, beta and gamma emission, 5.2.2b Deflection and ionising effects of nuclear radiation, 5.2.3a Radioactive decay, 5.2.3b Effects of decay on the nucleus and decay equations, 5.2.4a Half-life, 5.2.4b Choosing isotopes for applications, and 5.2.5 Effects of ionising radiation and safety precautions. Each one has a worked solution and a mark scheme showing where the marks go.