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    Equation of motion, functions

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    A simple harmonic oscillator, of mass m and natural frequency w_0, experiences an oscillating driving force f(t)=m a cos(wt). Therefore, its equation of motion is

    d^2x/dt^2 + w^2_0x = acos(wt)

    where x is the position. Given that at t=0 we have x=dx/dt=0, find the function x(t). Use BOTH with variation of the parameters and guessing methods. Describe the solution if w is approximately, but not exactly, equal to w_0. Give an example of a physical system where this happens.

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    https://brainmass.com/physics/resonance/equation-motion-functions-501040

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    The equation is:
    (1.1)
    The general solution is given by:
    (1.2)
    Where is the solution of the associated homogenous equation
    (1.3)
    and is a particular solution to equation (1.1).
    This equation is a second order linear equation with constant coefficients.
    To solve equation (1.3) we "guess" a solution in the form:
    (1.4)

    Plugging it in the homogenous solution we get:

    (1.5)
    Where
    Thus the two homogenous solutions are:
    (1.6)
    Since we are interested in real solutions, and the homogenous solution is a linear combination of these two linearly solutions, we can use Euler's identity
    (1.7)
    To express the two ...

    Solution Summary

    The expert examines equation of motion and functions.

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