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Help with trigonmetric function question

  1. Jun 4, 2004 #1
    This is a problem solving one, i just dont know where to start it though

    The speed of a particle in an alternating current is given by the equation:

    v = 3 cos t/3, where v is in cm/s and t is in seconds.

    The particle's movement begins at its point of equilibrium.
    How soon after the start would the particle first reach a displacement of
  2. jcsd
  3. Jun 4, 2004 #2


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    You are given an expression for the velocity, you need to find the displacement.

    [tex] v = \frac {dx} {dt} [/tex]


    [tex] \frac {dx} {dt} = 3 cos (\frac t 3) [/tex]

    [tex] \int dx = \int 3 cos (\frac t 3) dt[/tex]

    You should now be able to find an expression for the displacement as a function of time. You will need to find the time that satifies your conditions.
    Last edited: Jun 4, 2004
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