NEET Physics Nuclei Questions Solved


The half life period of 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

(a) X and Y have the same decay rate initially
(b) X and Y 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

(c) T1/2x=tmeany

0.693λx=1λyλx=0.693λy  or λx<λy

Also rate of decay = λN
Initially number of atoms (N) of both are equal but since λy>λx therefore, y will decay at a faster rate than x.

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