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Homework Help: Wave speed

  1. Sep 13, 2004 #1
    i've found 2 equations on longitudinal velocity of waves v=lambda*freq and v=Lsqrt(k/m). is the 2nd equation derived from the 1st? if not how do you derive it? thx.
  2. jcsd
  3. Sep 13, 2004 #2


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    The first is a general property of waves but the second appears to be based on the properties based on the properties of the medium. You gave no indication of what the physical situation is so it would be impossible to address derivation.
  4. Sep 14, 2004 #3
    oh lol.. i just found these 2 equations in my text book and was wondering how is the 2nd equation dervived... anyway thx for the reply
  5. Sep 14, 2004 #4

    Claude Bile

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    The first equation is just pure logic, the total distance travelled by a wave per second is just the number of cycles per second times the wavelength.

    The second equation is derived by modelling a medium as a series of discrete particles, then solving the equation of motion of these particles, which can then be used to derive a value for v using the wave equation.

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