Question

A student has a source of radiation that emits one of a, ß or y radiation. She places the

source opposite a Geiger-Müller tube and detector and records the count rate. She then
places a sheet of paper between the source and the detector and records the count rate,
and then repeats this with a sheet of aluminium instead of paper. Describe how her
results will allow her to work out which type of radiation is emitted by the source.

Please help :)

Answer 1

Beta radiation

Step-by-step explanation:

Radiation differs in its ability to penetrate a material (or air) - alpha particle has the least penetrating power and thus is stopped by the paper. Both beta and gamma particles have higher penetrating power than alpha - they passed through. However, radiation was stopped by a sheet of aluminium, which indicates a beta particles, since gamma radiation particles (photons) can easily pass through aluminium and some solid lead block is required to stop it.