Problem: Consider two parallel and large sheets with a surface area . One has a charge and the other is uncharged. Code (Text): q | | | | | | | | | | What would be the electric fields on the three regions as divided by the sheets ? General solution to problems like as told by my teacher: Using this principle, it is trivial to find a solution to this problem, distribution of charge: Code (Text): +q/2 +q/2 -q/2 +q/2 | | | | | | | | | | The surface charge densities and thus the electric field dictated by this distribution is indeed the correct answer. However, I really don't understand how/why this method works and my naive attempt at solving this problem comes out to be very wrong. Here's my attempt: The charge on one sheet would induce some charge of opposite polarity on the opposite end. I recall a similar situation where two conducting sheets have opposite charges, the charges are concentrated only on the inner surface resulting in 0 electric fields outside the sheets. Thus, I reason that the charge on the outer surfaces of both the sheets in this case would be 0, and on the inner surfaces it would be and respectively. So, someone please help, where did I go wrong ? How (or should I say 'Why') does my teacher's rule follow ?