Have a cubical box (sides all of length a) made of 6 metal plates which are insulated from each other. The left wall is located at y=-a/2,the right wall is at y=+a/2. Both left and right walls are held at constant potential V=V0. All four other walls are grounded. (Note that I've set up the geometry so the cube runs from x=0 to x=a, and from z=0 to z=a, but from y=-a/2 to y=+a/2 This should actually make the math work out a little easier!) Find the potential V(x, y,z) everywhere inside the box. Do your formulas give V=0 at the center of this cube? Is E=0 there? (Should they be??)