Physics · 2021
JEE Main · 25 July 2021, Shift 1 · Q5
Some nuclei of a radioactive material are undergoing radioactive decay. The time gap between the instances when a quarter of the nuclei have decayed…
Some nuclei of a radioactive material are undergoing radioactive decay. The time gap between the instances when a quarter of the nuclei have decayed and when half of the nuclei have decayed is given as :
(where $\displaystyle \lambda$ is the decay constant)
Official answer
(1)
$\displaystyle \frac{\ln \dfrac{3}{2}}{\lambda}$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.