The half-life of a radioactive nucleus is `50` days. The time interval `(t_2 -t_1)` between the time `t_2` when `(2)/(3)` of it has decayed and the time `t_1` when `(1)/(3)` of it had decayed is

Options

A. 50 days
B. 60 days
C. 15 days
D. 30 days

Answer

A

Explanation

* Radioactive substance disactive `2//3^(rd)` in time `t_(2)` and `1//3^(rd)` in time `t_(1)`.
* It becomes `(1)/(2)` when it disintegrate `2//3^(rd)` to `1//3^(rd)` so time `t_(2)-t_(1)` is half - life of substance.