Radioactivity and Alpha, Beta and Gamma Radiation

Unstable nuclei emit radiation to become more stable, either by emitting particles from the nucleus or energy in the form of gamma radiation.

  • Alpha radiation is made from two protons and two neutrons, it has a charge of +2 so is the most ionising

  • Beta radiation is a high speed electron emitted from the nucleus, it has a charge of -1 so is not as ionising as alpha

  • Gamma radiation it is a wave of energy, It has no charge so is the least ionising

Real Radioactive Sources

At some point you should see real radioactive sources demonstrated in the science lab. This video shows alpha, beta and gamma sources and some of their properties.

Activity and Count-rate

Activity is how many decays occur each second in a sample of radioactive material, while count-rate is what is picked up by a detector.

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