JEE Mains · Physics · STD 12 - 13. Nuclei
Two radioactive substances \(X\) and \(Y\) originally have \(N _{1}\) and \(N _{2}\) nuclei respectively. Half life of \(X\) is half of the half life of \(Y\). After three half lives of \(Y\), number of nuclei of both are equal. The ratio \(\frac{ N _{1}}{ N _{2}}\) will be equal to
- A \(\frac{1}{8}\)
- B \(\frac{3}{1}\)
- C \(\frac{8}{1}\)
- D \(\frac{1}{3}\)
Answer & Solution
Correct Answer
(C) \(\frac{8}{1}\)
Step-by-step Solution
Detailed explanation
\(T _{ x }= t ; T _{ y }=2 t\) \(3 T _{ y }=6 t\) \(N _{1}^{\prime}= N _{2}^{\prime}\) \(N _{1} e ^{-\lambda_{1} 6 t }= N _{2} e ^{-\lambda_{2} 6 t }\)…
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