Inverse Square Law

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All waves obey the square law. Gamma rays are waves.

All sources have an intensity, which means the per square metre. We treat a source as a point. At point zero, the is, in theory , but sources will have a definite size, therefore a definite intensity. If we double the distance from a source, the intensity goes down by times. This is because as the distance doubles, the area goes up four times.

A graph of the distance against the reciprocal of the count for a gamma source gives a line. It is a linear progression, but not . This is because the gamma source itself is deep in the source. We can work out from the where the source is.

It would not be desirable to have the source exposed directly to the room, as it would be possible to give oneself a massive dose of radiation. That could give radiation burns and increase the risk of .

The key to radiation safety is to keep oneself as far from the source as possible. This is why a source has to be handled with . Containers lined with are used for storage. The lead but does not completely stop the gamma radiation.

In the nuclear industry, highly radioactive sources are always handled remotely.