1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Group Velocity of light waves

  1. May 24, 2005 #1
    Dear Friends and Phorum,

    I need to know how to calculate the group velocity of light. I've read that's exactly "c", but I don't know how to calculate it.
  2. jcsd
  3. May 24, 2005 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    How about this?

    [tex]c=\lambda \nu = \frac{2\pi}{2\pi}\lambda \nu = \frac{\omega}{k}[/tex]

    So the dispersion relation is


    There you go

    [tex]v_g=\frac{d\omega}{dk} = c[/tex]
  4. May 24, 2005 #3
    Thanks You

    Thanks quasar987
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Group Velocity of light waves