A Geiger-Müller tube is used to measure the count rate from a radioactive isotope. The background count rate is measured to be 40 s-1 before the source is introduced. With the source in place, different absorbers are positioned between the source and the detector, and the raw count rates are recorded as follows:
| Absorber | Raw count rate / s−1\text{s}^{-1}s−1 |
|---|---|
| None | 840 |
| Paper | 340 |
| 5 mm aluminium | 40 |
| 5 cm lead | 40 |
Which types of radiation are being emitted by the isotope?
α\alphaα and β\betaβ
α\alphaα and γ\gammaγ
β\betaβ and γ\gammaγ
α\alphaα, β\betaβ and γ\gammaγ
128 exam-style questions on AQA A Level Physics Radioactivity (A-level only), covering Rutherford scattering (A-level only), $\alpha$ , $\beta$ and $\gamma$ radiation (A-level only), Radioactive decay (A-level only), Nuclear instability (A-level only), Nuclear radius (A-level only), Mass and energy (A-level only), Induced fission (A-level only), and Safety aspects (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.