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:
- 9 sec
- 55 sec
- 6 sec
- 12 sec
The Correct Option is A
Solution and Explanation
$\frac{1}{ T _{ eff }}=\frac{1}{ T _{1}}+\frac{1}{ T _{2}}$
$T _{ eff }=\frac{ T _{1} T _{2}}{ T _{1}+ T _{2}}$
$=\frac{1000}{110}=\frac{100}{11}=9.09$
$T _{ eff } \cong 9$
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Concepts Used:
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In the year 1911, Rutherford discovered the atomic nucleus along with his associates. It is already known that every atom is manufactured of positive charge and mass in the form of a nucleus that is concentrated at the center of the atom. More than 99.9% of the mass of an atom is located in the nucleus. Additionally, the size of the atom is of the order of 10-10 m and that of the nucleus is of the order of 10-15 m.
Read More: Nuclei
Following are the terms related to nucleus:
- Atomic Number
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- Atomic Mass Unit