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Interaction of light with a shockwave

  1. Jan 28, 2016 #1

    I am trying to understand how light would interact with a shockwave, but for that I need to make sure my understanding of the physics of light is correct.

    It is my understanding that light travels independent of a medium because of the electromagnetic waves it produces.

    A wave, such as a shockwave, requires a medium to travel through. Particles must bump into other particles to transmit the energy of the wave. If these two things travel in different medium how do they interact? They obviously must because we can see a shockwave when it forms.

    Does light simply slow down when it reaches the area of more dense particles that is the shockwave then speed back up, upon exit? Do they influence each other at all?

    Thanks for you input!
  2. jcsd
  3. Jan 28, 2016 #2


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    Not quite a direct answer to your question but for interest Google 'Schlieren images of shockwaves'
    Last edited: Jan 28, 2016
  4. Jan 28, 2016 #3
    The shockwaves that one can see sometimes around fighter planes are due to water droplets.

    The other thing (as in Schlieren photography) is caused by variation in the refractive index with density.
  5. Jan 28, 2016 #4
    No, the speed of light is different in different media. A vacuum can also be a "medium" for the transmission of electromagnetic waves, where they reach their maximum speed which we call c. In any other medium, the speed of light is less than c.
    "Simply" is probably going a bit far, but basically this is what happens, yes.
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