A radioactive nuclide can decay simultaneously by two different processes which have decay constants `lambda_(1)` and `lambda_(2)`. The effective decay constant of the nuclides is `lambda`.

Options

A. `lambda=lambda_(1)+lambda_(2)`
B. `lambda=(1)/(2)(lambda_(1)+lambda_(2))`
C. `(1)/(lambda)+(1)/(lambda_(1))+(1)/(lambda_(2))`
D. `lambda=sqrt(lambda_(1)lambda_(2))`

Answer

A

Explanation

As disintegration by two different processes is simultaneous, therefore, effective decay constant `lambda=(lambda_(1)+lambda_(2))`.