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A radioactive substance has a half-life ...

A radioactive substance has a half-life of 64.8 h. A sample containing this isotope has an initial activity `(t=0)` of `40muCi`. Calculate the number of nuclei that decay in the time interval between `t_1=10.0h` and `t_2=12.0h`.

Text Solution

Verified by Experts

The correct Answer is:
A, C, D
`R_(0)=lambdaN_(0)impliesN_(0)=(R_(0))/(lambda)`
where, `lambda=(In2)/(t_(1//2))`
`N=N_(0^(e-lambdat))`
Find `N_(1)=N_(0e^(-lambdat1))`
and `N_(2)=N_(0e^(-lambdat2))`
`:.` Number of nuclei decayed in given
time `=N_(1)-N_(2)`
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