COMEDK · Physics · 29. Nuclear Physics
\(15 / 16\) th of a radioactive sample disintegrates in \(2 \mathrm{~h}\). Mean life of radioactive sample is approximately
- A \(30 \mathrm{~min}\)
- B \(43 \mathrm{~min}\)
- C \(21 \mathrm{~min}\)
- D \(1.5 \mathrm{~min}\)
Answer & Solution
Correct Answer
(B) \(43 \mathrm{~min}\)
Step-by-step Solution
Detailed explanation
The undecayed nuclei in a radioactive sample are given by Given, \(\quad N=N_{0}-\frac{15}{16} N_{0}=\frac{1}{16} N_{0}, t=2 \mathrm{~h}\) \(\Rightarrow \quad \frac{N_{0}}{16}=N_{0}\left(\frac{1}{2}\right)^{\frac{2}{t_{1 / 2}}}\)…
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