Physics · 2018
JEE Main · 16 April 2018, Shift 1 · Q26
At some instant, a radioactive sample S_1 having an activity 5 μ Ci has twice the number of nuclei as another sample S_2 which has an activity of 10…
At some instant, a radioactive sample $\displaystyle \mathrm{S}_1$ having an activity $\displaystyle 5 \mu \mathrm{Ci}$ has twice the number of nuclei as another sample $\displaystyle \mathrm{S}_2$ which has an activity of $\displaystyle 10 \mu \mathrm{Ci}$. The half lives of $\displaystyle \mathrm{S}_1$ and $\displaystyle \mathrm{S}_2$ are :
Official answer
(1)
$\displaystyle 20$ years and $\displaystyle 5$ years, respectively
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JEE Main 2018 Physics question, with the answer from NTA’s final answer key. Where our answers come from.