JEE Mains · Physics · STD 12 - 13. Nuclei
A radioactive substance decays to \(\left(\frac{1}{16}\right)^{t h}\) of its initial activity in \(80\, days.\) The half life of the radioactive substance expressed in days is ... .
- A \(20\)
- B \(200\)
- C \(2\)
- D \(4\)
Answer & Solution
Correct Answer
(A) \(20\)
Step-by-step Solution
Detailed explanation
\(N_{o} \stackrel{t_{\frac{1}{2}}}{\longrightarrow} \frac{N_{o}}{2} \stackrel{t_{\frac{1}{2}}}{\longrightarrow} \frac{N_{o}}{4} \stackrel{t_{\frac{1}{2}}}{\longrightarrow} \frac{N_{o}}{8} \stackrel{t_{\frac{1}{2}}}{\longrightarrow} \frac{N_{o}}{16}\) \(4 \times t_{1 / 2}=80\)…
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