JEE Mains · Physics · STD 12 - 13. Nuclei
Half lives of two radioactive nuclei \(A\) and \(B\) are \(10\, minutes\) and \(20\, minutes\), respectively. If, initially a sample has equal number of nuclei, then after \(60\) \(minutes\) , the ratio of decayed numbers of nuclei \(A\) and \(B\) will be
- A \(9 : 8\)
- B \(1 : 8\)
- C \(8 : 1\)
- D \(3 : 8\)
Answer & Solution
Correct Answer
(A) \(9 : 8\)
Step-by-step Solution
Detailed explanation
\({{\text{N}}_{\text{A}}} = {{\text{N}}_{{\text{OA}}}}{{\text{e}}^{ - \lambda {\text{t}}}} = \frac{{{{\text{N}}_{{\text{OA}}}}}}{{{2^{t/{t_{1/2}}}}}} = \frac{{{{\text{N}}_{{\text{OA}}}}}}{{{2^6}}}\) \(\therefore\) Number of nuclei decayed…
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