H-atoms in ground state (13.6 eV) are excited by monochromatic radiation of photon of energy 12.1 eV. Find the number of spectral lines emitted in H-atom.

Answer

3

Explanation

`E_n = -13.6 + 12.1 =- 1.5 eV`
`E_n = (E_1)/(n^2) therefore n^2 = (E_1)/(E_n) = 9 , n = 3`
Spectral lines emitted `=(n(n-1))/(2) = 3`