AP EAMCET · PHYSICS · Nuclear Physics
Two radioactive materials \(\mathrm{Y}_1\) and \(\mathrm{Y}_2\) initially contain same number of nuclei. Their decay constants are \(9 \lambda \mathrm{s}^{-1}\) and \(6 \lambda \mathrm{s}^{-1}\) respectively. The time after which the ratio of number of undecayed nuclei of \(\mathrm{Y}_1\) and \(\mathrm{Y}_2\) becomes \(\frac{1}{e}\) is
- A \(\frac{1}{3 \lambda} \mathrm{s}\)
- B \(\frac{1}{15 \lambda} \mathrm{s}\)
- C \(\frac{1}{10 \lambda} \mathrm{s}\)
- D \(\frac{1}{8 \lambda} \mathrm{s}\)
Answer & Solution
Correct Answer
(A) \(\frac{1}{3 \lambda} \mathrm{s}\)
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Detailed explanation
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