The activity of a sample of radioactive material is `R_(1)` at time `t_(1)andR_(2)"at time"t_(2)(t_(2)gtt_(1))`. Its mean life is T. Then,

Options

A. `R_(1)t_(1)=R_(2)t_(2)`
B. `(R_(1)-R_(2))/(t_(1)-t_(2))`=constant
C. `R_(2)=R_(1)e^((t_(1)-t_(2))//T`
D. `R_(2)=R_(1)e^((t_(1)//t_(2))//T`

Answer

C

Explanation

Activity, `R=R_(0)e^(-lamdat),thereforeR_(1)=R_(0)e^(-t//T)`
`implies"Aganin",R_(2)=R_(0)e^(-t2//T)`
`therefore R_(2)=R_(1)e^(-t2//T)impliesR_(2)=R_(1)e^(((t_(1)-t_(2)))/(T))`