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Bottle. sound by blowing across the top

  1. Jul 2, 2014 #1
    sound created by blowing accross the top of the bottle produces sound due to standing waves created on air inside the bottle.

    why blowing inside the bottle does not produce sound but only across?

    how vibrations created on air inside the bottle propagate in space as they are separated from outside by the walls of bottle? or the walls of bottle start to vibrate?

    thank you
     
  2. jcsd
  3. Jul 2, 2014 #2

    A.T.

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    It does, but wrong with frequency to resonate.

    The bottle is open, isn't it?
     
  4. Jul 3, 2014 #3
    thanks A.T.

    why blowing across the top produces resonance while blowing in not?
     
  5. Jul 3, 2014 #4

    A.T.

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  6. Jul 3, 2014 #5

    CWatters

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    I believe this is to do with turbulence. The air flow is probably more turbulent when you blow across the edge of the bottle.
     
  7. Jul 3, 2014 #6

    A.T.

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    Yes. When the edge splits the air flow, it separates and creates a periodically repeating vortex pattern similar to the one seen below. The periodic pressure disturbances propagate as sound waves that can resonate.

    https://www.youtube.com/watch?v=bVNvH51CmlE
     
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