MCQ
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$.....sec$
- ✓$9$
- B$55$
- C$6$
- D$12$
✓
Answer
Correct option: A.
$9$
a
$\frac{1}{ T _{\text {eff }}}=\frac{1}{ T _{1}}+\frac{1}{ T _{2}}$
$\frac{1}{ T _{\text {eff }}}=\frac{1}{ T _{1}}+\frac{1}{ T _{2}}$
$T _{ eff }=\frac{ T _{1} T _{2}}{ T _{1}+ T _{2}}=\frac{1000}{110}=\frac{100}{11}=9.09$
$T _{ eff } \cong 9$
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