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Homework Help: Homework help please! Initial phase angle?

  1. Jun 28, 2008 #1
    A wave is propagating down a string having a diameter of 0.0013 m and a density of
    5240 kg/m3. The wave has the form y = A sin(k x - w t + beta)
    where A = 0.011 m, w = 59.8 rad/s, and k = 72.4 rad/m.
    the velocity of propagation of the wave is 0.825967 m/s

    The transverse speed @ y/@t is 0.177606 m/s at x = 0.0102762 m and t = 0.00385686 s.
    What is the initial phase angle beta if we assume that 0 < k x - w t + beta < pi ?
    Answer in units of rad.
     
  2. jcsd
  3. Jun 28, 2008 #2

    Redbelly98

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    What have you attempted so far towards solving this?
     
  4. Jun 28, 2008 #3
    i have used the formula.. zy/zt =wAcos((kx - wt + (beta))
    and solved for beta. i got an answer 0.78 and it was wrong.
     
  5. Jun 29, 2008 #4

    Redbelly98

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    Double-check your +/- signs, what's the derivative of -wt?

    You're on the right track.
     
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