Radioactive Decay And Nuclear Radiation (GCSE Physics)

Which of the following materials is most effective at stopping alpha particles?

Why are lead aprons or shields used when working with gamma emitters?

The half-life of a certain isotope is 10 minutes. Starting with 8000 atoms, how many atoms remain after 20 minutes (two half-lives)?

Which nuclear equation represents alpha decay of thorium-232 (write products as symbols and mass/atomic numbers conceptually)?

Which of these is a common medical use of gamma rays?

Which property correctly compares alpha, beta and gamma radiation in terms of ionising power and penetration (highest ionising ? lowest ionising)?

Which type of nuclear radiation consists of two protons and two neutrons and is the least penetrating?

A sample emits 500 counts per minute at 1 m distance. If the detector is moved to 2 m, approximately what count rate would be expected assuming a point source and inverse square law (neglecting background)?

What would be the effect on measured count rate if a thin sheet of aluminium is placed between a beta-emitting source and a GM detector?

Which definition of the becquerel (Bq) is correct?

Which absorber would most reduce gamma radiation intensity?