Two radioactive materials. |NUCLEAR PHYSICS| JEE MAIN 2019

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JEE MAIN_2019_

S2_100419

Question

Two radioactive materials A and B have decay constants $10 \lambda$ and $\lambda$, 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 $1 / \mathrm{e}$ after a time.

Select the correct option:

A

$\frac{1}{10 \lambda}$

B

$\frac{11}{10 \lambda}$

C

$\frac{1}{9 \lambda}$

D

$\frac{1}{1 \lambda}$

✓ Correct! Well done.

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