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RadiationRadiationLearning Outcomes

• Apply the term radiation to EM waves and alpha (α), beta (β) and gamma (γ), and know which are ionising.

• know that waste materials from nuclear power stations and nuclear medicine are radioactive

• be aware that the random nature of radioactive decay and its consequences

• distinguish between alpha (α), beta (β) and gamma (γ) radiation in terms of their penetrating power, relate their penetrating powers to their potential for harm

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RadiationRadiation

Key Words:

• Background radiation: The low level radiation that is present at all times from rocks/food/people/the sky etc.

• Random: Cannot be predicted.

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RadiationRadiation

Alpha

Beta Gamma

EM Radiation

Radiation

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RadiationRadiationWhat are Alpha, Beta and Gamma?

Alpha, Beta and Gamma are NUCLEAR radiation. They are produced by radioactive elements

Size Penetration Damage

Alpha Large Low High

Beta Medium Medium Medium

Gamma Small High Low

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RadiationRadiationIonisation

Alpha, Beta, Gamma, X-rays, and ultraviolet radiation are all ionising radiation.

Ionisation is when radiation removes an electron from an atom, if this happens to atoms in living cells it can be very dangerous and can break up DNA and can

destroy cells. This can eventually lead to cancer.

The more energy carried by a type of radiation, the more ionising it is. In general alpha is the most ionising, followed by beta, gamma, x-rays and

ultraviolet. The rest of the EM spectrum does NOT ionise cells.

Remember: Only Alpha Beta and Gamma are emitted from radioactive atoms!

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RadiationRadiationBackground Radiation

Rocks/Buildings

Nuclear waste and medical waste are sources of radiation and need to be buried deeply underground. Even after being buried they still contribute to background radiation. Background radiation is always present and at low levels. For the most part background radiation is not dangerous, although

radon gas is thought to be the second biggest cause of lung cancer!

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RadiationRadiationRadiation Experiments

Whenever performing experiments with radiation it is important to remember two things:

• Because background radiation is always present it usually needs to be accounted for by subtracting the background radiation from the results of your experiment.

• Because radiation is a random process it is important that you perform your experiments over a long enough time period to account for the randomness.

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RadiationRadiation

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RadiationRadiationPlenary

You are chief inspector at a nuclear power plant.You have been asked to produce a safety leaflet explaining the dangers of

nuclear waste to the public (and the workers).You must also explain how this waste is dealt with