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Homework Help: Traveling wave question

  1. Nov 17, 2004 #1
    A string has a linear mass density of 3.4 g/m. When a sinusoidal wave is created on the string with a speed of 32.8 cm/s the displacement of the particles on the string at x=13.3 cm varies with time according to the following equation: y=4.4sin[1.1-3.3 t] cm. Find the frequency.

    Well, I am stuck on this question and need a kick in the right direction...

    v=f*lambda
    angular velocity=2*3.14*f=wave#*velocity

    I really dont have a clue as to where to begin...
     
  2. jcsd
  3. Nov 17, 2004 #2

    James R

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    The equation of a travelling wave moving in the positive x direction is:

    [tex]y = A \sin(kx - \omega t)[/tex]

    where

    [itex]k[/itex] is the wave number
    [itex]\omega[/itex] is the angular frequency
    [itex]A[/itex] is the amplitude.
     
  4. Nov 17, 2004 #3
    the equation Im given doesnt have an x variable so am I to assume k= 1.1? or w=-3.3? And if w=-3.3 then the frequency would be a negative number? is that possible?
     
  5. Nov 17, 2004 #4

    James R

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    You're given x=13.3 cm.

    Also, w is not -3.3, but 3.3.
     
  6. Nov 17, 2004 #5
    oh ok, thanks for the help.
     
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