Can anyone help me to understand why equipotential surfaces must always be perpendicular to the electric field lines that pass through them?(adsbygoogle = window.adsbygoogle || []).push({});

My textbook gives what seems to be a simple mathematical explanation, but the logic is escaping me.

It states that dV= -E.ds= 0, (where the "." appears to be dot product of the two vectors-Eand dsand soEmust be perpendicular to the displacement of the equipotential surface.

I can understand that the dot product=0 means two vectors are perpendicular. I am looking for a more intuitive explanation to really understand what is going on.

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# Homework Help: Electric Field Lines homework

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