1. The problem statement, all variables and given/known data Two large parallel metal plates are oriented horizontally and separated by a distance 3d. A grounded conducting wire joins them, and initially each plate carries no charge. Now a third identical plate carrying charge Q is inserted between the two plates, parallel to them and located a distance d from the upper plate (a) What induced charge appears on each of the two original plates? (b) What potential difference appears between the middle plate and each of the other plates? Each plate has area A. 2. Relevant equations 3. The attempt at a solution I'm not sure how to even attempt the question, a) I don't know how the distance d is related to charge induced on the top and bottom since E fields between large parallel plates are uniform. What I do think, is that the magnitude of charge induced is equal to Q, by the principle of conservation of charge, but that's all i can come up with. b) My intuition tells me that using the equation C = ∈A/d and C = Q/V allows me to find the potential difference. Any help will be greatly appreciated.