The half-life period of a radio-active element `X` is same as the mean life time of another radio-active element `Y`. Initially they have the same number of atoms. Then:

Options

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

Answer

C

Explanation

`T_(X)=T_(Y)=1.44T_(Y)`
`because R=lambdaN` and N is same for both,
`therefore" "R_(X) lt R_(Y) or R_(Y) gt R_(X)`
`"i.e., Y will decay faster than X."`