A radioactive sample decays $\frac{7}{8}$ times its original quantity in 15 minutes. The half-life of the sample is
Solution
<p>$N = {{{N_0}} \over {{2^{{t \over {{T_{1/2}}}}}}}}$</p>
<p>$$ \Rightarrow {2^{{t \over {{T_{1/2}}}}}} = {{{N_0}} \over N} = {{{N_0}} \over {\left( {{{{N_0}} \over 8}} \right)}} = 8$$</p>
<p>$\Rightarrow {t \over {{T_{1/2}}}} = 3$</p>
<p>$\Rightarrow {T_{1/2}} = {{15} \over 3} = 5$ min</p>
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Radioactivity
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