E=hc/lambda... C

  1. I was thinking about refraction and phase velocity change, when i thought about whether the c in e=hc/lambda is always 3x10^8 or does it refer to the speed in the medium?
    Thanks
     
  2. jcsd
  3. Simon Bridge

    Simon Bridge 14,912
    Science Advisor
    Homework Helper
    Gold Member

    in ##E=hc/\lambda## ##c## is always the speed of light in vacuum.
    if the speed in the medium is important, it will show up in equations as a refractive index.
    as far as the photon is concerned, the "medium" is an array of atoms with empty space in between.
     
  4. So if wavelength decreases in a refractive medium, does that mean energy increases???
     
  5. Simon Bridge

    Simon Bridge 14,912
    Science Advisor
    Homework Helper
    Gold Member

  6. It depends on what do you mean by λ. It is the wavelength in vacuum or in the medium?
    Anyway, you should have the formula getting back to E=hf which is valid in vacuum and media as well.
     
  7. Cheers folks. I now see that the qm and wave models must be evaluated differently and that E=hf is a more useful formula to employ :).
     
Know someone interested in this topic? Share a link to this question via email, Google+, Twitter, or Facebook

Have something to add?