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igcse physics notesprinted 119 · PDF 119
124 pagesrevision 46936
printed 119 · PDF 119
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Beta radiation is used to measure thickness of papers in industry. The
paper is subjected to beta radiation and a detector is placed on the other
side of the paper to check if the beta radiation coming through at the other
end is standard.
Gamma rays can be used in fault detection in metal pipes. If there is a fault
in the pipework the radiation will escape through it.
Food decay can also be prevented by irradiation, which means killing the
microbes that cause decay using intense gamma rays.
In the same way, surgical instruments can be sterilized by being sealed in
plastic bags and then exposed to gamma rays to kill any microbes. Gamma
radiation is used because it can penetrate through the plastic bag without it
needing to be opened.
Cancer can also be diagnosed and treated through gamma rays. The
gamma rays are aimed at the tumor to kill cancerous cells and destroy the
tumor.
Safety Precautions for radiation
Ionizing nuclear radiation can be very harmful to us. It can cause the cell to
die, cause harmful mutations and growth of tumors and lead to cancer or
even affect genes of future generations if the mutation happens in a
gamete cell.
Radioactive materials are thus held with care. Radioactive sources are
stored and moved in lead covered storage boxes to absorb most of the
radiation, and usually have a tiny opening to give out radiation in a small
range.
Safety precautions for radioactivity include:
Wear Protective Suits in contaminated areas: The suit absorbs radiation
and different materials can be used depending on the type of radiation you
are being exposed to.
Radioactive hazard labels: This is done to warn people of the danger so
that they can stay far away from the source of radiation and try not to be
near it for too much time.