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The half life of a radioactive element i...

The half life of a radioactive element is `10` days, if the mass of the specimen reduces to `1//10^(th)` then the time taken is :-

A

`100` days

B

`50` days

C

`33` days

D

`16` days

Text Solution

Verified by Experts

The correct Answer is:
C
`N = N_(0)e^(-lambdat) rArr (N_(0))/(10) = N_(0)e^(-lambdat) rArr ln(1) - ln(10) = - lambdat`
`rArr t = ((ln10)/(ln2)) T_(1//2) rArr t = 33` days
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