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

A particle of mass m and charge q is attached to a spring with force constant k, hanging from the ceiling. Its equilibrium position is a distance h above the floor. It is pulled down a distance d below equilibrium and released, at time t = 0;

Under the usual assumptions (d << lambda << h) calculate the intensity of the radiation hitting the floor as a function of the distance R from the point directly below q.

2. Relevant equations

3. The attempt at a solution

I see that this is a harmonic oscillator that could be described by x(t) = d cos(wt)

and a = -w*w*dcos(wt)

I would like to use Larmor's formula: P = u_0 q^2 a^2 / ( 6 pi m c) but I believe that I may need to revert back the to Poynting vector because we are only trying to find intensity [W/area] so: S = u_0 q^2 a^2 / ( 32 pi m c).

I think I'm having a hard time determining how to draw the picture to visualize this situation. How do I handle finding the intensity on the floor? I see that the distance from the mass to the floor is (R^2 + (h+delta)^2)^1/2.

Does anyone have any tips on how to get started with this? Do I need to rewrite the electric and magnetic fields and recalculate the Poynting vector from scratch (re-derive the electric dipole equations essentially?)

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# Homework Help: EM Radiation oscillating charged mass

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