There are three main types of radiation, called alpha, beta and gamma radiation, which all have different properties.
The nuclei of radioactive atoms are unstable. They break down and change into a completely different type of atom. This is called radioactive decay.
The radioactivity of an object is measured by the number of nuclear decays it emits each second – the more it emits, the more radioactive it is.
There are two definitions of half-life, but they mean essentially the same thing. Half-life is the time taken for:
- The number of nuclei of the radioactive isotope…