A radioactive substance emits n beat particles in the first 2 s and `0.5` n beta particles in the next 2 s. The mean life of the sample is

Monjur Alahi

A radioactive substance emits n beat particles in the first 2 s and `0.5` n beta particles in the next 2 s. The mean life of the sample is
A. 4 s
B. 2 s
C. `(2)/((1n 2))`
D. 2 (1n 2) s


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Salim Ahmed Kawsar

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Correct Answer - C
We have, `lamda=(0.693)/(T_(1//2)`
Mean life, `tau=(1)/(lamda)=(t_(1//2))/(0.693)=(2)/(2.303log_(2))=(2)/(In2)s`

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