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Homework Help: Understanding Velocity in Waves

  1. Dec 14, 2011 #1
    1. The problem statement, all variables and given/known data
    I was told that a string on a guitar vibrates at a frequency of 110 Hz. The length of the string is .648 m and the tension is 100 N. I was told to find the mass per unit length, μ, of the string. Although I got the correct answer, I was wondering why my initial attempt was incorrect (shown below).

    2. Relevant equations
    [itex]f_{n}[/itex] = [itex]\frac{n}{2L}v[/itex]

    [itex]v[/itex] = [itex]\sqrt{\frac{T}{μ}}[/itex]

    3. The attempt at a solution
    dakdX.jpg

    (Sorry for the formatting, I don't type in latex really quickly).

    In this case, if it's a guitar, why is the velocity of the wave not equivalent to 345 m/s (343.2 m/s)? Why is it so much lower (142.56 m/s)?

    Thank you.
     
  2. jcsd
  3. Dec 14, 2011 #2
    Oh, is the velocity referring to the velocity of the vibrating string?

    I think I understand now.
     
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