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JEE MAIN 2021
27-07-21 S1
Question
If ' f ' denotes the ratio of the number of nuclei decayed $\left(N_d\right)$ to the number of nuclei at $t=0\left(N_0\right)$ then for a collection of radioactive nuclei, the rate of change of ' $f$ ' with respect to time is given as : [ $\lambda$ is the radioactive decay constant]
Select the correct option:
A
$-\lambda\left(1-e^{-\lambda t}\right)$
B
$\lambda\left(1-e^{-\lambda t}\right)$
C
$\lambda \mathrm{e}^{-\lambda \mathrm{t}}$
D
$-\lambda e^{-\lambda t}$
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
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