Lorentz force and Newton's law

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v_pino
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Homework Statement



This problem asks you to work out the dielectric function of a gas of particles with number density n, charge q, and mass m, with a steady magnetic field applied in the z direction.

Assume an electric field in the x direction,

[tex]E_x(t)=E_xe^{-i \omega t}[/tex]

is applied. Write down the x and y components of the Newton’s Law using the Lorentz force equation and no damping. Assume a solution for the velocity of the form,

[tex]v_x(t)=v_{x0}e^{-i \omega t}[/tex]

and

[tex]v_y(t)=v_{y0}e^{-i \omega t}[/tex]

Solve for v_x0 and v_y0 in terms of E_x and the cyclotron frequency,

[tex]\omega_c = qB/m[/tex]

Homework Equations



[tex]\mathbf{F}=q(\mathbf{E}+\mathbf{v}\times \mathbf{B})[/tex]

[tex]\mathbf{F}=m \mathbf{a}[/tex]

The Attempt at a Solution



[tex]m \frac{d \mathbf{v}}{dt}=q(\mathbf{E}+\mathbf{v}\times \mathbf{B})[/tex]

[tex]\frac{dv_x}{dt}=-i \omega v_{x0}e^{-i \omega t}[/tex]

[tex]\frac{dv_y}{dt}=-i \omega v_{y0}e^{-i \omega t}[/tex]

I am having trouble pulling all these equations to write out the components of Newton's law.
 
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I am not sure how to solve for v_x0 and v_y0 in terms of E_x and the cyclotron frequency. Any help would be greatly appreciated!