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Homework Help: Transverse wave through a wire, and tension.

  1. Apr 18, 2010 #1
    A transverse wave in a wire with a linear density 2.35 g/m has the form y(x,t) = (1.4 cm)sin[(5.45 m-1)x−(6950 s-1)t].
    What is the tension?


    I took the A=.014m, k=5.45 /m, and [tex]\omega[/tex]=6950.

    I used the formula for the max velocity = A[tex]\omega[/tex]
    v=(.014)(6950)=97.3

    Then I used the formula for the speed of a wave on a string v=[tex]\sqrt{\frac{F}{M/L}}[/tex].
    97.3=[tex]\sqrt{\frac{F}{.00235}}[/tex]

    And I got F=22.24813

    This was not the correct answer. I would appreciate any advice.

    I attempted to find the velocity of the pulse : (0.943s)(3.29m)(8)=24.81976
     
  2. jcsd
  3. Apr 18, 2010 #2
    Try using this equation for velocity:

    v=[tex]\omega[/tex]/k
     
  4. Apr 18, 2010 #3
    Am I right in assuming that 6950 is omega? The problem says 6950 /s, not radians/s. Is this still omega?
     
  5. Apr 18, 2010 #4
    Yes, that is still omega.
     
  6. Apr 18, 2010 #5
    That worked, thank you very much.
     
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