JEE Mains · Physics · STD 12 - 13. Nuclei
For a certain radioactive process the graph between \(In\, {R}\) and \({t}\,({sec})\) is obtained as shown in the figure. Then the value of half life for the unknown radioactive material is approximately \(....\,{sec}.\)
- A \(6.93\)
- B \(4.62\)
- C \(2.62\)
- D \(9.15\)
Answer & Solution
Correct Answer
(B) \(4.62\)
Step-by-step Solution
Detailed explanation
\({R}=R_{o} e^{-\lambda t}\) \(\ell n R=\ell n R_{o}-\lambda t\) \(-\lambda\) is slope of straight line \(\lambda=\frac{3}{20}\) \(t_{1 / 2}=\frac{\ell n 2}{\lambda}=4.62\)
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