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Why we can't hear ?

  1. Apr 11, 2012 #1
    If sound travels faster in solids than in air then why on closing our ears we cannot hear the sound properly?
     
  2. jcsd
  3. Apr 11, 2012 #2

    haruspex

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    It may be faster in a solid but be absorbed more. Also, every change in medium tends to absorb/reflect some sound.
     
  4. Apr 12, 2012 #3
    I'm no sound engineer, but I also doubt that hands make a good sound conductor. They are soft and flexible, and that just doesn't sound good when talking about sound transmission.

    As haruspex said, they'll block/ reflect/ absorb most of the sound trying to get through them. But, whatever small fraction of sound that is left over will go through them faster.
     
  5. Apr 12, 2012 #4

    sophiecentaur

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    Land animals spent hundreds of millions of years developing ears that are sensitive to sound vibrations in air. The ear drum is a very light structure which is joined to the inner ear by those little bones (ossicles) and 'matches the vibrations to the actual sensor (cochlea). If you put your massive and absorbant finger in the way, it can't move as freely as the ear drum and only passes a small proportion of the sound energy that hits it. The speed isn't what counts - its the fact that the sound just doesn't get through.
     
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