An apparatus is used to determine the nature of the emissions from a radioactive source in a vacuum. Different absorbers can be placed between the source and the detector.
The table shows the results obtained with this apparatus:
| Absorber in use | Count rate on detector (counts per second) |
|---|---|
| None | 600 |
| Thin paper | 250 |
| 1.0 mm aluminium | 250 |
| 1.0 cm lead | 20 |
Which types of radiation are being emitted by the radioactive source?
α\alphaα-particles and β\betaβ-particles
α\alphaα-particles and γ\gammaγ-rays
β\betaβ-particles and γ\gammaγ-rays
α\alphaα-particles only
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.