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JEE MAIN 2021
25-02-21 S1
Question
Two radioactive substances $X$ and $Y$ originally have $N_1$ and $N_2$ nuclei respectively. Half life of $X$ is half of the half life of $Y$. After three half lives of $Y$, number of nuclei of both are equal. The ratio $\frac{N_1}{N_2}$ will be equal to:
Select the correct option:
A
$\frac{1}{8}$
B
$\frac{3}{1}$
C
$\frac{8}{1}$
D
$\frac{1}{3}$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
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