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Homework Help: Do sound waves and light rays interact?

  1. Jul 20, 2008 #1
    1. The problem statement, all variables and given/known data

    see topic title

    2. Relevant equations

    I think that sound waves are vibrations of particles in a medium. The vibrations continue until the energy is gone. Sound seems to need a medium to travel through.

    Light can travel in a vacuum. your eye sees it from a source or from an object (reflection, refraction)...

    3. The attempt at a solution

    see my thoughts above. My guess is that they don't interact, but I'm not sure why exactly I think this.
  2. jcsd
  3. Jul 20, 2008 #2


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    They do interact in that light interacts with the medium it is travelling through and sound waves can change that medium.
    So you could change the density of a gas with sound waves and the change in density would give a (small) chnage in refractive index.

    There are acousto-optical modulators where sound waves in specialy chosen materials are used to change the direction of a light beam by changing the optical properties of the material.
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