P6 - OCR Additional Science PHYSICS

P6 Radioactive Materials

Atoms and Elements

The nucleus is made up of PROTONS and NEUTRONS.

An atom always has the same number of protons, but it doesn’t always have the same number of neutrons these are called isotopes

Ionising Radiation

There are three types of ionising radiation;

Alpha

Beta

Gamma

They emit these radiations because of radioactive decay; this takes places because an atom is unstable.

Alpha decay

It emits a helium atom made up of 2 protons and 2 neutrons.

Beta decay

It’s where the atom changes neutron into a proton and an electron, this electron ejects from the nucleus – this is the beta radiation

Gamma decay

After alpha or beta decay, a nucleus sometimes contains surplus energy. It emits this as gamma radiation. During gamma decay only energy is emitted. This decay doesn’t change the type of atom.

Background Radiation

If a person is exposed to radiation they known as irradiated, if radioactive material is on their skin, body or clothes they are contaminated.

Dangers of Radiation

Alpha is the most dangerous if the source is inside the body, as it can be absorbed…