(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The equation of motion of a free electron in an electric field is

m((d^2)x)/(dt^2) = -eE (Eq. 1)

If x and E have the time dependence exp(iwt), where w=angular frequency, then

-(w^2)mx = -eE (Eq. 2)

What does the time dependent function whose second derivative equals -(w^2)x look like?

3. The attempt at a solution

I know from my papers that the electromagnetic wave is given by

E=E0exp(iwt),

and I guess the equation I'm after looks similar. The second derivative of x*exp(iwt) would give me the correct answer, but x=x0*exp(iwt) doesn't seem to do, because equation 2 says x and not x0.

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# Homework Help: Need the correct time dependent function

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