The half-life period of a radioactive element X is same as the mean life of another radioactive element Y Initially, both of them have the same numbers of atoms then

Options

A. X wil decay faster than Y
B. Y will decay faster than X
C. Y and X have same decay rate initially
D. X and Y decay at same rate always

Answer

B

Explanation

Given that `(T_(1//2))_(x) = (T_(av))_(gamma)`
`rArr (0.693)/(lambda_(x)) = (1)/(lambda_(y)) rArr lambda_(y) (1)/(0.693) lambda_(x)`
`rArr lambda_(y) = 1.44 lambda_(x) rArr R_(y) = 1.44 R_(x)`
As decay rate of Y is more than the element `X_(i)` hence Y will decay faster than X.