Notes...

If you read the source code, you can see that i used electrostatics (i.e. Coulomb's law) to calculate the force between charges, potential, etc. This is ok for statics charges, but if you have moving charges, this is not quite correct. For example, i should use Lorentz's force instead Coulomb's law, or, in other words, do not forget the magnetism (a moving charge has a magnetic field). But if the velocity is low (as in my computer) , that can be neglected and the error in doing that is very small (in fact, the magnetism is a relativistic effect) . So, what i'm trying to say is that there is not difference for the naked eye between a properly (in a physical sense) done applet an this applet.
But, if you want to do it right, ok, take the source and use it, but don't forget that an accelerated charge emits radiation. That affect it's speed (the enery is conservated), and don't forget the retarded potentials :) and there is more...


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