GCSE Physics

Alpha Particles

These are the biggest and heaviest form of radiation. They are made of four particles: two protons and two neutrons:
Alpha Particle
Since there are two protons present, alpha particles have a 2+ charge. This makes it easy for them to interact with matter. So does their size.

They are easily stopped by most things - paper, or a few centimetres of air would be enough.

Sometimes we say that the alpha particle is a helium nucleus, as it is exactly the same thing.

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