JEE Mains · Physics · STD 12 - 13. Nuclei
The half-life of a radioactive nucleus is \(5\) years, The fraction of the original sample that would decay in \(15\) years is
- A \(\frac{1}{8}\)
- B \(\frac{1}{4}\)
- C \(\frac{7}{8}\)
- D \(\frac{3}{4}\)
Answer & Solution
Correct Answer
(C) \(\frac{7}{8}\)
Step-by-step Solution
Detailed explanation
\(15\) year \(=3\) half lives Number of active nuclei \(=\frac{N_0}{8}\) Number of decay \(=\frac{7 N _0}{8}\)
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