A student measures the radiation count rate from three different radioactive sources, XXX, YYY, and ZZZ, using a Geiger-Müller (GM) tube and counter. To identify the type of radiation emitted, different absorbing materials are placed between the source and the detector.
The table below shows the measured count rates in counts per minute (cpm):
AbsorberNo source (background)Source XSource YSource ZNone25480650320Thin sheet of paper2447826322Aluminium sheet (5 mm)262325318 \begin{array}{|l|c|c|c|c|} \hline \textbf{Absorber} & \textbf{No source (background)} & \textbf{Source } X & \textbf{Source } Y & \textbf{Source } Z \\ \hline \text{None} & 25 & 480 & 650 & 320 \\ \hline \text{Thin sheet of paper} & 24 & 478 & 26 & 322 \\ \hline \text{Aluminium sheet (5 mm)} & 26 & 23 & 25 & 318 \\ \hline \end{array} AbsorberNoneThin sheet of paperAluminium sheet (5 mm)No source (background)252426Source X48047823Source Y6502625Source Z320322318Based on these results:
Identify which source emits only alpha radiation\textbf{only alpha radiation}only alpha radiation and explain your choice.
Identify which source emits only beta radiation\textbf{only beta radiation}only beta radiation and explain your choice.
Practise AQA GCSE Physics Atoms and nuclear radiation with exam-style questions for Foundation and Higher tier. 21 questions covering Radioactive decay and nuclear radiation, Nuclear equations, Half-lives and the random nature of radioactive decay, and Radioactive contamination, matched to the AQA GCSE Physics (8463) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.