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A radioactive substance decays to 1/16 t...

A radioactive substance decays to `1/16 th` of the initial mass in 40 days. The half life of the substance is….. Day.

A

20

B

10

C

5

D

2.5

Text Solution

Verified by Experts

The correct Answer is:
B
`N/N_0=1/16=1/2^4`
`therefore 1/2^n=1/2^4 therefore n=4`
Now `n=t/t_(1//2) implies t_(1//2)=t/n=40/4=10 days`
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