Home
Class 12
PHYSICS
The half-life of a radioactive substance...

The half-life of a radioactive substance is 30 min. The time (in minutes) taken between `40%` decay and `85%` decay of the same radioactive substance is

A

15

B

30

C

45

D

60

Text Solution

Verified by Experts

The correct Answer is:
D
`D.P_(1)=40%impliesA.P_(1)60%impliest_(1)`
`D.P_(2)=35%T_(1//2)log_(10)((1)/(A.P_(1)))`
`t_(2)=3.32T_(1//2)log_(10)((1)/(A.P_(2)))`
`t_(2)-t_(1)=3.32T_(1//2)[log_(10)((A.P_(1))/(A.P_(2)))]`
`=3.32xx30[log_(10)((60//100)/(15//100))]`
`=3.32xx30log_(10)4`
`=3.32xx30xx2log_(10)2`
`=59.95`
=60
Promotional Banner

Similar Questions

Explore conceptually related problems

The half-life of a radioactive substance is 30 minutes, The time (in minutes) taken between 40 % decay and 85 % decay of the same radioactive substance is.

Define half-life of a radioactive substance.

The half life of a radioactive substance is 13 years. The decay constant is

Half life of a radio-active substance is 20 minutes. The time between 20 % and 80 % decay will be

The half life of a substance is 20 minutes. E The time interval between 33% decay and 67% decay.

The half - life of a radioactive substance is 50 days. The substance will disintegrate completely in

The half-life period of a radioactive substance is 5 min . The amount of substance decayed in 20 min will be

The half life of radioactive element is 20 min . The time interval between the stages of its 33% and 67% decay is

A radioactive substance takes 20 min to decay 25%. How much time will be taken to decay 75% :

The half life of a radioactive substance is 20s, the time taken for the sample to decay by 7//8^(th) of its initial value is