Physics · 2021
JEE Main · 25 February 2021, Shift 1 · Q19
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…
Two radioactive substances $\displaystyle X$ and $\displaystyle Y$ originally have $\displaystyle N_1$ and $\displaystyle N_2$ 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 $\displaystyle \frac{\mathrm{N}_1}{\mathrm{~N}_2}$ will be equal to :
Official answer
(3)
$\displaystyle \frac{8}{1}$
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