Question
A radioactive sample disintegrates via two independent decay processes having half lives $T _{1 / 2}^{(1)}$ and $T _{1 / 2}^{(2)}$ respectively. The effective half- life $T _{1 / 2}$ of the nuclei is
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Answer
$\lambda_{ eq }=\lambda_{1}+\lambda_{2}$
$\frac{1}{ T _{1 / 2}}=\frac{1}{ T _{1 / 2}^{(1)}}+\frac{1}{ T _{1 / 2}^{(2)}}$
$T _{1 / 2}=\frac{ T _{1 / 2}^{(1)} T _{1 / 2}^{(2)}}{ T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}}$
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