The energy of an excited H-atom is `-3.4eV`. Calculate angular momentum of `e^(-)`

Options

A. `2.11xx10^(-34)J-s`
B. `3.34xx10^(-32)J-s`
C. `3.34xx10^(-30)J-s`
D. None of these

Answer

A

Explanation

Given, `F_(en)=-3.4eV`
Use, `E_(n)=(-13.6)/(n^(2))eV`
`implies -3.4=(-13.6)/(n^(2))eV`
`implies n^(2)=(13.6)/(3.4)=4implies n=2`
Angular momentum `=(nh)/(2pi)=(2xx6.63xx10^(-34))/(2xx3.142)=2.11xx10^(-34)J-s`