1. Limited time only! Sign up for a free 30min personal 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!

Frequency of Sound and Light waves

  1. Aug 8, 2012 #1
    Sorry for another dumb question. Thank you in advance.

    What factors effect the frequency of sound and light waves. Light waves are effected by electromagnetic energy and given by (f=E/h) right? What about sound waves?

    Also, to make sure, even though ultraviolet light has much more energy infrared light and hence a proportionally greater frequency and lower wavelength, they both travel at 3*10^8 in air. All light travels at 3*10^8 in air, right?
  2. jcsd
  3. Aug 8, 2012 #2

    Simon Bridge

    User Avatar
    Science Advisor
    Homework Helper

    Taken backwards
    - the speed of light in a vacuum is a constant ... but, in a media, it can depend on the wavelength.
    The speed of light in air is very close to that in vacuum so we usually just pretend it's the same.

    The energy carried by a photon in determined by the frequency and plancs constant ... not the energy of the light wave. You have to be careful about confusing different models - one is classical and the other quantum mechanical.

    The "wave" of light is oscillations in the electro-magnetic field strength in space. The wave of sound is oscillations in the pressure of the air.
  4. Aug 8, 2012 #3
    got it. thank you.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook