Physics · 2019
JEE Main · 10 April 2019, Shift 1 · Q26
Two radioactive materials A and B have decay constants 10 λ and λ, respectively. If initially they have the same number of nuclei, then the ratio of…
Two radioactive materials A and B have decay constants $\displaystyle 10 \lambda$ and $\displaystyle \lambda$, respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of A to that of B will be $\displaystyle 1$/e after a time :
Official answer
(4)
$\displaystyle \frac{1}{9 \lambda}$
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JEE Main 2019 Physics question, with the answer from NTA’s final answer key. Where our answers come from.