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Technological Hazard >>
Radiation hazard >>Nature of radioactivity, types of radiation |
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Nature of radioactivity, types of radiation Interaction
radiation with matter Radiation sources,
natural and artificial radiation Nuclear and
radiological accidents, protection measures |
Radioactive decay is the ability of some nucleus to be spontaneously
transformed into another nucleus or into the same nucleus with less energy.
The extra energy is released by emitting particles (alpha, beta, gamma, neutron or others). Atom structure All materials are composed of atoms. An atom consists
of a positive charged nucleus and negatively charged electrons, enclosing it.
The atom has no electronic charge. In 1911 Ernest Rutherford showed that mass of the
atoms was mainly concentrated (99.9%) in the nucleus. The size of an atom approximately equals to 10- Charge of nucleus equal to number of protons in
nucleus. Number of protons and neutrons in nucleus called atomic mass number
A.
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