JEE Mains · Physics · STD 12 - 13. Nuclei
At some instant, a radioactive sample \(S_1\) having an activity \(5\,\mu Ci\) has twice the number of nuclei as another sample \(S_2\) which has an activity of \(10\,\mu Ci.\) The halflives of \(S_1\) and \(S_2\) are
- A \(10\) years and \(20\) years, respectively
- B \(5\) years and \(20\) years, respectively
- C \(20\) years and \(10\) years, respectively
- D \(20\) years and \(5\) years, respectively
Answer & Solution
Correct Answer
(B) \(5\) years and \(20\) years, respectively
Step-by-step Solution
Detailed explanation
Given \(: \mathrm{N}_{1}=2 \mathrm{N}_{2}\) Activity of radioactive substance \(=\lambda \mathrm{N}\) Half life period \(\mathrm{t}=\frac{\ln 2}{\lambda}\) or, \(\lambda=\frac{\ln 2}{\mathrm{t}}\)…
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