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Physics · 2017
JEE Main 2017 · 2017-04-02 Offline · Q26
A radioactive nucleus A with a half life T, decays into a nucleus B. At t =0, there is no nucleus B. At sometime t, the ratio of the number of B to…
A radioactive nucleus A with a half life T, decays into a nucleus B. At $\displaystyle \mathrm{t}=0$, there is no nucleus B. At sometime t, the ratio of the number of $\displaystyle B$ to that of $\displaystyle A$ is $\displaystyle 0.3$ . Then, t is given by :
Official answer
(2)
$\displaystyle \mathrm{t}=\mathrm{T} \frac{\log 1.3}{\log 2}$
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