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# Divergence theorem

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1. I learned the continuity equation.
▽(Dot)J = - partial (lo)v / partial t

I just thought about the things learned last time and remembered divergence theorem and it looks like I can put (sigma)E instead of J.
But the result was not right. I think this may not work. Do you know why it doesn't work? Or where I made a mistake?
2. (Original post by KoreanStudent)
I learned the continuity equation.
▽(Dot)J = - partial (lo)v / partial t

I just thought about the things learned last time and remembered divergence theorem and it looks like I can put (sigma)E instead of J.
But the result was not right. I think this may not work. Do you know why it doesn't work? Or where I made a mistake?
Hi, it doesn't work because the J takes into account the total current density, whereas the relation between J and E takes into account only the free current density.

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