JEE Mains · Physics · STD 12 - 13. Nuclei
The half life period of radioactive element \({x}\) is same as the mean life time of another radioactive element \(y.\) Initially they have the same number of atoms. Then:
- A \({x}\)-will decay faster than \({y}\).
- B \({y}\) - will decay faster than \({x}\).
- C \({x}\) and \({y}\) have same decay rate initially and later on different decay rate.
- D \({x}\) and \({y}\) decay at the same rate always.
Answer & Solution
Correct Answer
(B) \({y}\) - will decay faster than \({x}\).
Step-by-step Solution
Detailed explanation
\(\left(t_{1 / 2}\right)_{x}=(\tau)_{y}\) \(\Rightarrow \frac{\ell n 2}{\lambda_{x}}=\frac{1}{\lambda_{y}} \Rightarrow \lambda_{x}=0.693 \lambda_{y}\) Also initially \({N}_{{x}}={N}_{{y}}={N}_{0}\) Activity \({A}=\lambda {N}\) As…
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