Question

H-atom is exposed to electromagnetic radiation of $\lambda =1025.6\mathring{A}$ and excited atom gives out induced radiations. What is the minimum wavelength of these induced radiations?

• A. $102.6$ nm
• B. $12.09$ nm
• C. $121.6$ nm
• D. $810.8$ nm

Answer 1

Answer: (A)

$102.6$ nm

$△E=\frac{hc}{\lambda }=\frac{1240eV-nm}{1025.6\times {10}^{-10}\times {10}^9}$
$△E=12.09eV$
In three different radiations, minimum wavelength for $3\to 2$ transition.
${\lambda }_{3-1}=\frac{hc}{△E}\Rightarrow \frac{1240eV-nm}{12.09eV}\approx 102.6nm$