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A potentially retarded question.

  1. Oct 3, 2007 #1
    What's the speed limit for sound? As I understand sound itself is not composed of particles that move themselves but a transfer of energy between particles which then oscillate and produce the sound phenomenon. If so do relativistic changes affect sound moving at high rates at all, as there really is no single particle that sound is contributed to. Could sound theoretically travel faster than light does in a vaccuum, under correct circumstances? Obviously sound can't travel in a vacuum but i'm thinking some super dense material.

    I hope this wasn't a question with some trivial, fairly obvious answer. ehehe..
    Any educated replies will be much appreciated.
     
  2. jcsd
  3. Oct 3, 2007 #2
    Partial answer: Ultimately, the transfer of energy between the molecules in the acoustic medium is mediated by electromagnetic forces, so the speed of sound cannot exceed the speed of light.
     
  4. Oct 15, 2007 #3
    The speed limit varies for sound as does the density of the medium. The particles do move. They wiggle. In space called a wave. In time, a vibration.
     
  5. Oct 16, 2007 #4
    Another potentially retarded question: How fast is the speed of sound in one proton? If I push on one side of the proton how long will it take before the opposite side moves in that direction?
     
  6. Oct 16, 2007 #5

    Hootenanny

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    :cry:
     
  7. Oct 16, 2007 #6
    You speak of philosophical concepts as if material. Can we "see" an electron? Not ever.
    A proton? Same answer.

    Is this true? The Doppler frequency change made by you going away from a sound source is the same as the shift made by the sound source going away from you.

    Is this true? The Doppler frequency change made by you going away from a light source
    is the same as the shift made by the light source going away from you.

    Understand the correct answers and maybe you will zero in somewhat on your problem.
    I am trying to get these concepts figured out myself.
     
  8. Oct 16, 2007 #7

    rcgldr

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    Note that speed of sound is slower than the speed of molecules. For air at around 20 degreees centrigrage, the speed of the molecules is 502m/s while the speed of sound is 343m/s. Then there's alway wiki:

    http://en.wikipedia.org/wiki/Speed_of_sound
     
  9. Oct 16, 2007 #8
    Is this true? The Doppler frequency change made by you going away from a sound source is the same as the shift made by the sound source going away from you.

    Is this true? The Doppler frequency change made by you going away from a light source
    is the same as the shift made by the light source going away from you.


    The first statement is false and the second true.
     
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