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The half life of a radioactive substance...

The half life of a radioactive substance is 30 days. What is the time taken to disintegrate to `3//4^(th)` of its original mass ?

A

30 days

B

15 days

C

60 days

D

90 days

Text Solution

Verified by Experts

The correct Answer is:
C
Here, `(N_0-N)/N_0=3/4` or `N/N_0=1/4=(1/2)^2`
`therefore` No of half lives, n=2
Time taken to disintegrate = Half life x No. of half lives
= 30 x 2 =60 days
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Knowledge Check

  • The half-life of a radioactive substance is 10 days. This means that

    A
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    B
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    D
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    B
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