What does omega mean in the photon energy derivation?

Join the discussion
Registration is free. Start your own thread to ask a follow-up.
3 replies · 2K views
Randomchemstudent
Messages
4
Reaction score
0
Homework Statement
w/v=c,w=vc giving E=hcv
Relevant Equations
E=hw, lamda*w=c, wavenumber (v) = 1/lamda
So I'm a chemistry student here in the UK - and I'm feeling a bit like a fish out of water on a physics forum but... I'm having trouble with a derivation that seems simple but i can't for some reason seem to understand.

I know that the energy of a photon is given by E=hc and that c=lambda*v giving E=hc/lamda. But my lecturer has used w(omega) in his derivation and i don't understand what it means and why he's used it to derive the energy in this way.

Any help would be much appreciated!
 
Physics news on Phys.org
##\omega## is angular frequency. It differs from frequency by a factor of ##2\pi##.
 
  • Like
Likes   Reactions: Randomchemstudent
Spectroscopists often use ω for frequency, or for wavenumber. They (we) often loosely talk about wavenumber as frequency, e.g. "a frequency of 1730 cm-1". For example, on the NIST website, molecular vibrational frequencies in cm-1 are given the symbol ω. So you have to be a bit careful.
 
  • Like
Likes   Reactions: PeroK
Randomchemstudent said:
Problem Statement: w/v=c,w=vc giving E=hcv
Relevant Equations: E=hw, lamda*w=c, wavenumber (v) = 1/lamda

I know that the energy of a photon is given by E=hc
No. The energy of a photon is ##hf##, which is often written as ##h \nu##, where ##f## or ##\nu## is the frequency. You seem to have your notation mixed up.