Ionising Radiation
Quantum and Nuclear

Are alpha particles radioactive?

Teaching Guidance for 14-16 Supporting Physics Teaching

Is it correct to say that alpha particles are radioactive?

Wrong Track: The radioactive material gives out alpha particles, which are radioactive and therefore can do harm to human tissue, causing cancers.

Right Lines: The source gives out alpha particles. Each alpha particle consists of two protons and two neutrons. The alpha particles are potentially dangerous as they can disturb the molecular composition of human tissue, increasing the risk of cancer.

Alpha particles are not radioactive

Thinking about the learning

Some students attribute the property of being radioactive to alpha or beta particles.

Thinking about the teaching

The important point to stress here is that alpha particles are not in themselves radioactive. Each alpha particle consists of two protons and two neutrons and that's it. The particles do not have some mysterious, additional property of being radioactive.

Teacher Tip: The alpha particles are the radiation: nothing more, nothing less!

Ionising Radiation
is used in analyses relating to Radioactive dating
can be analysed using the quantity Half-Life Decay Constant Activity
features in Medical Physics
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