Problem

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 that kept first time. If now their present activities are

A_1

and

A_2

respectively, then their age difference equals a.

\frac{T}{\ln 2} \ln \frac{2A_1}{A_2}

T \ln \frac{A_1}{A_2}

\frac{T}{\ln 2} \ln \frac{A_2}{2A_1}

T \ln \frac{A_2}{2A_1}

Browse the problem library