What is a radioactive substance?

What three types if radiations are given out from a radioactive substance?

When does a radioactive source give out radiation(radiation decay)?

Where does background radiation come form?

Why was the plum pudding model of the atom rejected?

What is an isotope?

How far can each type of radiation travel in air?

How can we separate a beam of alpha, beta and gamma radiation?

Why are alpha, beta and gamma radiation dangerous?

What do we mean by the 'half-life' of a radioactive source?

What do we mean by the activity of a radioactive source?

What happens to the activity of a radioactive isotopes as it decays?

How do we choose a radioactive isotopes for a particular job?