Radioactivity

A radioactive nucleus is unstable and will emit radiation. There are 3 main types.

Alpha

• Strongly ionising
• Only travels a few centimetres in air
• Stopped by a thin sheet of paper

Beta

• Ionising Radiation
• Penetrates card or several sheets of paper
• Stopped by a 3mm hick sheet of aluminium or other metal

Gamma

• Weakly ionising
• Very Penetrating
• Reduced significantly by a thick lead sheet or blocks of concrete

Ionising Radiation - Radiation that has enough energy to break molecules or atoms into charged particles called ions.

Ionisation - The molecules or atoms lose electrons

After ionisation the ions can then take part in chemical reactions -> ionising radiation damages living cells.

It kills them / damages their DNA in the cell so that the cells mutates into a cancer cell, which then grows in an uncontrolled manner.

Ionising radiation:

• Alpha
• Beta
• Gamma (from the radioactive nuclei)
• X-Rays
• Ultra-Violet Radiation