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Homework Help: Find the oscillation amplitude

  1. Dec 12, 2008 #1
    1. The problem statement, all variables and given/known data
    A 2.0 m long string vibrates at its second harmonic frequency with a maximum amplitude of 2.0cm. One end of the string is at x = 0cm. Find the oscillation amplitude at x = 10,20,30,40, and 50cm.

    2. Relevant equations

    A(x) = 2asin(kx)
    k= 2pi/wavelength

    3. The attempt at a solution
    I tried plugging the numbers into the equatio, but couldn't get the right answer. Can someone get me on the right track?
  2. jcsd
  3. Dec 12, 2008 #2
    I'm not sure why you have a two in your equation for Amplitude. Because you're on the second harmonic, the total 2m leingth of the string is your wavelength. The 2.0 cm is your amplitued a. Plug and solve without the 2.
    Also, make sure you use consistant units. Change your cm to meters.
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