COMEDK · Physics · 29. Nuclear Physics
A sample of a radioactive element whose half-life is 30 s contains a million nuclei at a certain instant of time. How many nuclei will be left after \(10 \mathrm{~s}\) ?
- A \(7.96 \times 10^{5}\)
- B \(3.78 \times 10^{5}\)
- C \(1.11 \times 10^{5}\)
- D \(1.26 \times 10^{5}\)
Answer & Solution
Correct Answer
(A) \(7.96 \times 10^{5}\)
Step-by-step Solution
Detailed explanation
Half-life of radioactive sample, \[ T_{1 / 2}=30 \mathrm{~s}, N_{0}=10^{6} \] If \(N\) be the remaining number of nuclei after \(t=10 \mathrm{~s}\), then according to radioactive decay law,…
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