The discovery of radioactivity by the French physicist Henri Becquerel in 1896 is generally taken to mark the beginning of 20th-century physics.

The beams are aimed at the tumour from many different directions to maximise the dose on the tumour but to minimise the dose on the surrounding soft tissue.

The term applies to all types of radiation including radiation from the can damage living cells.

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Doctors also use radioactive sources for a number of reasons, eg: Sterilisation of surgical instruments.

This is done by considering: (long enough for the isotope to produce useful measurements, but short enough for the radioactive sources to decay to safe levels soon after use) If the half-life chosen is too long, the damaging effects of the radiation would last for too long and the dose received would continue to rise.

Uses of alpha radiation.

Like Thomson’s discovery of the electron, the discovery of radioactivity in uranium by French physicist Henri Becquerel in 1896 forced scientists to radically change their ideas about atomic structure.

Smoke from a fire absorbs alpha radiation, altering the ionisation and triggering the … In…

Radioactive sources can be very useful but need handling carefully to ensure safety. Irradiation can be used to preserve fruit sold in supermarkets by exposing the fruit to a emitted by the cobalt will destroy any bacteria on the fruit but will not change the fruit in any significant way. Sterilisation can be done without high temperatures.It can be used to kill bacteria on things that would melt.It can be very harmful - standing in the environment where objects are being treated by irradiation could expose people’s cells to damage and

Ionisation is useful for smoke detectors.

Our editors will review what you’ve submitted and determine whether to revise the article.Such radioisotopes as cobalt-60 and cesium-137 are widely used to treat cancer.

This technique can damage healthy tissue, so careful calculations are done to establish the best dose - enough to kill the tumour but not so much so that the healthy tissue is damaged.In medical applications that involve using radioactive sources, efforts are made to ensure that irradiation does not cause any long-term effects.

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Radioisotopes can be used for medical purposes, such as checking for a blocked kidney.

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Uses of Radiation.

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Nuclear radiation ionises materials. Radioactive americium releases alpha radiation, which ionises the air inside the detector.

Radioisotopes have found extensive use in diagnosis and therapy, and this has given rise to a rapidly growing field called nuclear medicine. The nuclei of most everyday atoms are stable—that is, they do not change over time. This can be put to good use as well as being a hazard.

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