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What exactly is sound?

  1. Dec 6, 2008 #1
    What exactly is SOUND ? I have read in many books as describing it as the energy carried by fluctuation of air pressure of correct extent & rapidity or compression & rarefaction of air molecules but i want to know what exactly happens at micro level , at atomic level , out of curiousity what will happen when atoms or electron collide , is sound produced , can it be measured ? Is it a property of macro level ? IS friction necessary to produce sound ?
  2. jcsd
  3. Dec 6, 2008 #2


    Staff: Mentor

    Re: Sound

    Do you understand what pressure is "at a micro level"? If so, then sound is essentially just a wave in the pressure.

    Friction is not really relevant to sound. Basically friction is due to shear stress, while pressure is due to normal stress.
  4. Dec 6, 2008 #3


    User Avatar
    Science Advisor

    Re: Sound

    Sound is like touch. Touch is movement sensed by your skin, sound is movement sensed by your ear.
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