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In 8000 y, a radioactive substance reduc...

In 8000 y, a radioactive substance reduces a `1/32`th part of its initial amount. Determine its half-life.

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Let initial amount of radioactive substance be 1 and half-life is T.

`therefore` According to question,
5T=8000 or , `T=8000/5`=1600 y
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