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Equation for simple harmonic motion

  1. Mar 30, 2004 #1

    dom

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    i was just wondering if anybody knew where i could find the equation for simple harmonic motion (SHM). I have found loads but not the right one. i need the one that starts... y=e(^-3wnt)*Asin(wdt)+(Asin(wt)/SQRT(l-(w^2/wn^2)^2+... anyone got any ideas? got assignment to hand into uni tomorrow and i need it bad :biggrin:
     
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  3. Mar 30, 2004 #2
    :confused: I never saw any equation for SHM that starts like that. The ones I know are:
    [tex]x(t) = A\cos (\omega t + \phi)[/tex]
    [tex]v(t) = -A\omega \sin (\omega t + \phi)[/tex]
    [tex]a(t) = -A\omega ^2 \cos (\omega t + \phi)[/tex]
     
  4. Mar 30, 2004 #3

    Integral

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    I looks to me like you have a specific solution to a specific problem. It appears to be a case of damped ossiliations, but in no way is it an equation that you will find on the web. If you could post the specifics of the problem it is a solution to we may be able to help you. We need the original DE and the initial conditions.
     
  5. Mar 30, 2004 #4

    dom

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    its an equasion for the vibration of a ball on a spring, i am comparing my excel model to the one i made on a program called working drawing.
     
  6. Mar 30, 2004 #5

    Integral

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    The equation you posted is the solution to a Differential Equation with initial values. Without this information, I do not see how we can reproduce the solution. What are the initial conditions, what is the damping function. (your solution is damped) Is there a driving function? Without these details we cannot reproduce the solution.
     
    Last edited: Mar 30, 2004
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