1. The problem statement, all variables and given/known data Two square parallel sheets with area>>distance between them have total charges of Q1 and Q2 on them. What is the force between them? 2. Relevant equations Q1in+Q2in=0 Q1in+Q1out=Q1 Q2in+Q2out=Q2 Q1out=Q2out 3. The attempt at a solution I set up 4 equations for the charges on the inner and outer sides of each plate (shown above) Now I have no idea how to find the electric field from here. any help?