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Resonant Frequency of Air

  1. Sep 20, 2015 #1
    When an object vibrates next to another object with the same resonant frequency it causes it to vibrate with it. Why is it that when an object vibrates, it always causes the surrounding air to vibrate with it?
  2. jcsd
  3. Sep 20, 2015 #2
    Air supports vibrations over a very broad range of frequencies.
  4. Sep 20, 2015 #3


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    look close up at the vibrating object and the air that is in contact with it
    as the object vibrates back and forward, what do you think is happening to that air ?

    This is how sound waves are produced, say, from a loud speaker where the vibration of the speaker cone
    causes compression and rarefaction pressure waves in the air

    Last edited: Sep 20, 2015
  5. Sep 20, 2015 #4
    If the two objects are in contact, the second vibrates even if not at resonant frequency. Even if there is some air in between the second vibrates as well. It's only that at resonance the power transfer between the objects is higher.
    So your question does not really have a justification. The air vibrates because is in contact with a vibrating source. There is no need for resonance for this.
    A medium like air does not have a resonance unless is restricted to some closed volume which will impose boundary conditions.
  6. Sep 20, 2015 #5


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    The air surrounds the object, so when the object vibrates the air must move with it. The same thing happens for water or any other fluid medium. Or a solid medium if the vibrating object is in the ground.
  7. Sep 24, 2015 #6


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    Vibration can cause energy to be transferred between two objects. The special case of resonance is just the frequency at which energy transfer is at a maximum.
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