Okay so i have been looking at this question for about 2 days now and using all of my notes and resources but i can't find out what n equals. So if somebody could help me understand the concept of it then I think I could do this.
A hydrogen atom in an excited state emits a photon of frequency ν = 2.924 x 1015 s-1. If the electron returns to the ground state, in which level was it before the photon was emitted?
n =