JEE Mains · Physics · STD 12 - 13. Nuclei
A radioactive nucleus decays by two different processes. The half life for the first process is \(10\, s\) and that for the second is \(100 s\). the effective half life of the nucleus is close to\(.....sec\)
- A \(9\)
- B \(55\)
- C \(6\)
- D \(12\)
Answer & Solution
Correct Answer
(A) \(9\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{ T _{\text {eff }}}=\frac{1}{ T _{1}}+\frac{1}{ T _{2}}\) \(T _{ eff }=\frac{ T _{1} T _{2}}{ T _{1}+ T _{2}}=\frac{1000}{110}=\frac{100}{11}=9.09\) \(T _{ eff } \cong 9\)
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