A certain substance decays to `1//32` of its initial activity in `25` days. Calculate its half-life.

A certain substance decays to `1//32` of its initial activity in `25`

1.	A certain substance decays to `1//32` of its initial activity in `25` days. Calculate its half-life.
Answer» `1goverset(1)rarr(1)/(2)goverset(2)rarr(1)/(4)goverset(3)rarr(1)/(8)g overset(4)rarr(1)/(16)g` `overset(5)rarr(1)/(32)g :. n=5` `(n) =(t)/(t_(1//2))rArrt_(1//2)=(t)/(n)=(25)/(5) , t_(1//2)=5 "days"`

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A certain substance decays to `1//32` of its initial activity in `25` days. Calculate its half-life.

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