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A radioactive substance contains 10^15 a...

A radioactive substance contains `10^15` atoms and has an activity of `6.0xx10^11` Bq. What is its half-life?

Text Solution

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The correct Answer is:
A, C
`R_0=lambdaN_0`
`6.0xx10^11=lambda(10^15)`
`:.` `lambda=6.0xx10^(-4)s`
`t_(1//2)=(1n2)/lambda=(0.693)/(6.0xx10^-4)`
`=1.16xx10^3s`
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  • The activity of a radioactive source initially is 1600 Bq and after 8 s the activity falls to 100 Bq. What is its activity at time t=6s ?

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    B
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    C
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    D
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