AP EAMCET · PHYSICS · Nuclear Physics
A radioactive substance has a half-life of \(10^8\) years and an activity of \(10^4 \mathrm{~Bq}\). The number of atoms of this substance present is
- A \(9.1 \times 10^{19}\)
- B \(6.7 \times 10^9\)
- C \(4.5 \times 10^{19}\)
- D \(5 \times 10^{20}\)
Answer & Solution
Correct Answer
(C) \(4.5 \times 10^{19}\)
Step-by-step Solution
Detailed explanation
Half-life of a radioactive substance, \(\begin{aligned} T_{1 / 2} & =10^8 \text { years } \\ & =10^8 \times 365 \times 24 \times 60 \times 60=3.15 \times 10^{15} \mathrm{~s} \end{aligned}\) Activity, \(R=10^4 \mathrm{~Bq}\) Let \(N\) be the number of atoms of substance, then we…
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