Modern Physics 3 Question 16

16. 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

(1999, 3M)

(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

Show Answer

Solution:

  1. (t1/2)x=(tmean )y

 or 0.693λx=1λyλx=0.693λyλx<λy

or 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.



जेईई के लिए मॉक टेस्ट

एनसीईआरटी अध्याय वीडियो समाधान

दोहरा फलक