An excited state of H atom emits a photon of wavelength `lamda` and returns in the ground state. The principal quantum number of excited state is given by:

Options

A. `sqrt(lamdaR(lamdaR-1))`
B. `sqrt((lamdaR)/((lamdaR-1)))`
C. `(1)/(sqrt(lamdaR(lamdaR-1)))`
D. `sqrt(((lamdaR-1))/(lamdaR))`

Answer

B

Explanation

`(1)/(lamda)=R[(1)/(n_(1)^(2))-(1)/(n_(2)^(2))]=R[(1)/(1)-(1)/(n_(2)^(2))]`
`n_(2)=sqrt((lamda)/(lamdaR-1))`