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Homework Help: ?'s about simple harmonic

  1. Oct 25, 2004 #1
    Are all periodic motions simple harmonic? Why or why not? What is an example of a periodic motion that is not simple harmonic?
     
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  3. Oct 25, 2004 #2

    arildno

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    1. No; there's a lot of periodic motion which is not simple harmonics.
    For example:
    A swinging pendulum is not a simple harmonic oscillator.
    The earth's motion around the sun is periodic, but not that of a simple harmonic..
     
  4. Oct 25, 2004 #3

    Tom Mattson

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    A simple harmonic motion function has only a single frequency, as follows:

    x1(t)=Asin(ωt)

    Question: What happens when you add the following 2 harmonics together?

    x(t)=x1(t)+x2(t)=Asin(ωt)+Asin(2ωt)

    What is the period of this motion? What does the graph of x vs t look like?

    The answers to those questions should get you started.
     
  5. Oct 25, 2004 #4

    arildno

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    Just to state what is ordinarily meant by a PERIODIC function:
    We say that a function f is periodic in t with period T, if it exists a constant T so that
    f(t)=f(t+T) (for all choices of t)
     
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