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The count rate from 100 cm^3 of a radio...

The count rate from 100 `cm^3` of a radioactive liquid is c.Some of this liquid is now discarded. The count rate of the remaining liquid is found to be c/10 after three half-lives. The volume of the remaining liquid, in `cm^3` , is

Text Solution

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Initial count rate (CR) for 1 `cm^3` of liquid `=c/100`
After 3 half - lives , CR for 1 `cm^3` of liquid `=1/(8)xxc/100`
Let the volume of the remaining liquid `=V cm^3`
CR of this liquid `=V xxc/(800)=c/10 " or " V = 80`
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