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How to derive coulomb's law using gauss law
(edited 10 years ago)
Reply 1
Original post by Namod
I'm trying to derive the vector field E=14πϵ0qrr3\vec{E} = \frac{1}{4\pi\epsilon_0}\frac{q\vec{r}}{r^3} surrounding a point charge, starting with SEdA\oint_S \vec{E} \cdot \mathrm{d}\vec{A}. My uneducated guess would be to get the magnitude of the electric field from gauss' law, then integrate to get the scalar potential, before taking the gradient to get the vector field. Is there a more elegant way to achieve this?

Thanks.

James


Can you use a symmetry argument to say that the field must be radial and thus the vector field must be in the direction of r, so once you've got the magnitude from gauss's law, you're home and hosed?
Reply 2
What?

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