Question

From a radioactive substance `n_1` nuclei decay per second at an instant when total number of nuclei are `n_2`. Find half-life of the radioactive substance.

Answer 1

Correct Answer - A::B
Using the equation,
`-((dN)/(dt))=lambdaN`
We have, `n_1=lambda n_2`
:. `lambda = n_1/n_2`
Now, half-life is given by
`t_(1//2) = (1n2)/(lambda) = (1n2)/((n_1//n_2))`
`=(n_2/n_1)1n2`