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The Epic Interactive Encyclopedia 1998
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Epic Interactive Encyclopedia, The - 1998 Edition (1998)(Epic Marketing).iso
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Half-life
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INFOTEXT
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1992-09-02
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520b
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13 lines
During radioactive decay, the time in which
the strength of a radioactive source decays
to half its original value. It may vary from
millionths of a second to billions of years.
Radioactive substances decay exponentially;
thus the time taken for the first 50% of the
isotope to decay will be the same as the time
taken by the next 25%, and so on. In theory,
the decay process is never complete and there
is always some residual radioactivity. For
this reason, the half-life rather than the
total decay time is measured.