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JEE Mains · Physics · STD 12 - Dual nature of radiation and matter
- JEE Mains 2018
- Medium
- MCQ
Both the nucleus and the atom of some element are in their respective first excited states. They get de-excited by emitting photons of wavelengths \(\lambda _N,\,\lambda _A\) respectively. The ratio \(\frac{{{\lambda _N}}}{{{\lambda _A}}}\) is closest to
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(10^{-6}\)
Step-by-step Solution
Detailed explanation
Energy \(E = \frac {hc}{\lambda };\)
\(\frac{{{\lambda _N}}}{{{\lambda _A}}} = \frac{{{E_A}}}{{{E_N}}}\)
where \(E_A\) and \(E_N\) are energies of photons from atom and nucleus respectively. \(E_N\) is of the order of \(MeV = 10^6\,\,eV\) and \(E_A\) in few \(eV.\)
So \(\frac{{{\lambda _N}}}{{{\lambda _A}}}\, = \,{10^{ - 6}}\)
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