A radioactive material of half-life `T` was kept in a nuclear reactor at two different instants. The quantity kept second time was twice of the kept first time. If now their present activities are `A_1` and `A_2` respectively, then their age difference equals
A radioactive material of half-life `T` was kept in a nuclear reactor at two different instants. The quantity kept second time was twice of the kept first time. If now their present activities are `A_1` and `A_2` respectively, then their age difference equals
A
`T_(ln2)|ln'(A_(1))/(A_(2))|`
B
`T|ln'(A_(1))/(A_(2))|`
C
`T_(A)/(ln2)|ln'(A_(2))/(2A_(1))|`
D
`T|ln'(A_(2))/(2A_(1))|`
Text Solution
Verified by Experts
The correct Answer is:
C
`A_(1)=lambda^(-lambda(t_(1)-t_(2))) implies "ln" (2A_(1))/A_(2)=-lambda Deltatimplies Deltat= (T"ln" A_(2)/(2A_(1)))/(ln2)`
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Knowledge Check
Two rods A and B are of equal lengths. Their ends are kept at the same temperature difference and their area of cross - sections are A_(1) and A_(2) and thermal conductivities k_(1) and k_(2) . The rate of heat transmission in two rods will be equal, if . . . .. . .
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