The half - line period a radioactive element `X` is same as the mean life time of another radioactive element `Y`. Initially both of them have the same number of atoms. Then:

Options

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

Answer

c

Explanation

Half life of x = mean life of y
Let `lambda_(x) andlambda_(y)` be decay constants of x and y then conditon (1) implies
`(0.696)/(lamdba_(x))=(1)/(lambda_(y))rArr(lambda_(x))/(6.693)rArrlambda_(y)gtlambda_(x)`
As rate of decay `alphalamdba`, hence decay of y will be faster than that of x.