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JEE Mains · Physics · STD 12 - 13. Nuclei
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
- A None of the above
- B \(T _{1 / 2}= T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}\)
- C \(T _{1 / 2}=\frac{ T _{1 / 2}^{(1)} T _{1 / 2}^{(2)}}{ T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}}\)
- D \(T _{1 / 2}=\frac{ T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}}{ T _{1 / 2}^{(1)}- T _{1 / 2}^{(2)}}\)
Answer & Solution
Correct Answer
(C) \(T _{1 / 2}=\frac{ T _{1 / 2}^{(1)} T _{1 / 2}^{(2)}}{ T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}}\)
Step-by-step Solution
Detailed explanation
\(\lambda_{ eq }=\lambda_{1}+\lambda_{2}\) \(\frac{1}{ T _{1 / 2}}=\frac{1}{ T _{1 / 2}^{(1)}}+\frac{1}{ T _{1 / 2}^{(2)}}\) \(T _{1 / 2}=\frac{ T _{1 / 2}^{(1)} T _{1 / 2}^{(2)}}{ T _{1 / 2}^{(1)}+ T _{1 / 2}^{(2)}}\)
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