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Homework Help: Simple harmonic motion equation

  1. Nov 16, 2007 #1
    1. The problem statement, all variables and given/known data

    An object is undergoing simple harmonic motion. The graph shows the position of the object as a function of time. What is the first time after t = 0 s when the speed reaches a maximum?


    2. Relevant equations

    I don't know what equation to use to figure this out. φ = φo + wt perhaps?

    3. The attempt at a solution

    Im told that position at t=0 gives phi_0. But still do not know how to use the equation nor figure out any of the variables. Help is needed!
  2. jcsd
  3. Nov 17, 2007 #2


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    Homework Helper

    From the graph we get the following information. At t = 0 x = 1.5 cm, maximum displacent = 3cm, and period = 2s.
    Wright the equation of simple harmonic motion x = Asin(wt + phi). In this put A = 3cm, t = 0 and x = 1.5 cm find phi. Next take derivative of the equation, which gives the velocity and put it equal to zero. And find t.
    Last edited: Nov 17, 2007
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