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A sample of radioactive substance loses ...

A sample of radioactive substance loses half of its activity in `4 days`. The time in which its activity is reduced to `5%` is

A

12 days

B

`8.3` days

C

`17.3` days

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C
`kt=ln""(100)/(5) t=(2.303xxt_(1//2)xxlog 20)/(0.693)=4.324xxt_(1//2)=17.3` days.
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