A radioactive source emits α-particles, β-particles and γ-radiation.

1. (a)(i)State which type of radiation produces the strongest ionising effect.[1]
2. (a)(ii)State which type of radiation is deflected most by a magnetic field.[1]
3. (b)(i)Fig. 9.1 shows a Geiger-Müller (G.M.) tube and counter. A radioactive source is placed 10cm from the G.M. tube. In Fig. 9.2 a piece of metal 5mm thick is placed between the source and the G.M. tube. The readings on the counter have been corrected for background radiation and show the count rate due to the source. [Figure 9.1] [Figure 9.2] Explain how the readings show that the source emits β-particles and γ-radiation.[3]
4. (b)(ii)State why the readings cannot be used to show that the source emits α-particles.[1]
5. (c)Describe one way that a radioactive source is moved safely in a school laboratory.[1]