A radioactive substance emit 100 beta particfles in the first 2 s and 50 beta particles in the next 2s. The mean life of the sample is

Monjur Alahi

A radioactive substance emit 100 beta particfles in the first 2 s and 50 beta particles in the next 2s. The mean life of the sample is
A. 4 s
B. 2 s
C. `(2)/(0.693)s`
D. `2xx0.693 s`


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Salim Ahmed Kawsar

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Correct Answer - C
Given in 1st two seconds `100beta` particles and in next two seconds `50beta` particles are emitted.
`:.T_(1//2)=2s`
Hence, mean life, `T=(t_(1//2))/(0.693)=(2)/(0.693)`

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