Three fourth of active decays in a radioactive sample in 3/4, sec . half life of sample is

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13.Nuclei

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Three fourth of the active decays in a radioactive sample in $3/4\, sec$. The half life of the sample is

A

$\frac{1}{2}\,sec$

B

$1 \,sec$

C

$\frac{3}{8}\, sec$

D

$\frac{3}{4}\, sec$

Solution

(c) $\frac{3}{4}th$ active decay takes place in time

$t = 2\,({T_{1/2}})$

==> $\frac{3}{4} = 2\,({T_{1/2}})$

==> ${T_{1/2}} = \frac{3}{8}\sec $

Standard 12

Physics

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