Question

The rate of radioactive decay of a sample are `3 xx 10^(8) dps` and `3 xx 10^(7) dps` after time `20 min` and `43.03 min` respectively. The fraction of radio atom decaying per second is equal to
A. `A. (1)/(600)`
B. `B. 1`
C. `C. 0.5`
D. `D. 0.001`

Answer 1

Correct Answer - A
`k=(2.303)/(t_(2)-t_(1))log. (r_(1))/(r_(2))=(2.303)/(23.03)log.(3xx10^(8))/(3xx10^(7))= 0.1min^(-1)`
`k = -(dN//N)/(dt) = 0.1 min^(-1) = (1)/(600)s^(-1)`