Physics - Modern Physics Question with Solution | TestHub

Electron goes to its first excited state $(\mathrm{n}=2)$ from ground state $(\mathrm{n}=1)$ after absorbing $10.2\mathrm{eV}$ energy $$\begin{array}{l}\therefore \text{ Increase in momentum }=\frac{\mathrm{h}}{2\pi }\\ =\frac{6.6\times 10^{-34}}{6.28}\\ =1.05\times 10^{-34}\mathrm{J}-\mathrm{S}\end{array}$$