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(7)/(8)th of nuclei have been disintegra...

`(7)/(8)th` of nuclei have been disintegrated in 2 minutes after fresh sample was prepared. The half life of the sample is

A

30 seconds

B

1 minute

C

40 seconds

D

20 seconds

Text Solution

Verified by Experts

The correct Answer is:
C
2 minutes=3half life
1 half life `=(120)/(3)` =40sec
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