1. The problem statement, all variables and given/known data An infinite sheet of charge is located in the y-z plane at x = 0 and has uniform charge denisity σ1 = 0.57 μC/m2. Another infinite sheet of charge with uniform charge density σ2 = -0.39 μC/m2 is located at x = c = 28.0 cm.. An uncharged infinite conducting slab is placed halfway in between these sheets ( i.e., between x = 12.0 cm and x = 16.0 cm). What is V(S) - V(P), the potentital difference between point P, located at (x,y) = (6.0 cm, 0.0 cm) and S, located at (x,y) = (22.0 cm, -16.0 cm)? https://www.smartphysics.com/Content/Media/Images/EM/06/h6_planeA.png [Broken] 2. Relevant equations 3. The attempt at a solution I have attempted at an answer and obtained the result of 8685.87 V. This answer came by way of: Electric field at point P: E = (σ1/2ε)-(σ2/2ε) = 54286.72 (N/C) or (V/m) Set this point to be the zero potential energy position, and since the electrical field is constant, or so I thought, in the x direction, with no component in the y direction, I simply took the difference in x positions of the two points. 22cm-6cm= 16cm, therefore the ΔV between these two points is (54286.72V/m)*(.016m)= 8685.87 V The feedback to this answer says that I need to account for the Electric field not being constant between these two points. What I am confused about is that I thought the electric field between these two points would be constant. Since a single infinite plate will have a constant electric field that is not dependent on distance from the plate I assumed that the electric field between two of these plates would also be constant. Thank you to anyone that can explain this to me, I can't seem to figure it out and its driving me crazy.