An array of four charges is arranged along the x-axis at intervals of d = 4.8 m. The y-axis bisects the distance between q2 and q3.
(a) If two of the charges are +0.5 µC and two are -0.5 µC, draw a configuration of these charges that minimizes the potential energy at x = 0.
(b) If three of the charges are the same, q = +0.5 µC, and the charge at the far right is -0.5 µC, what is the potential at the origin?