Figure shows a thin plastic bar on the x axis. The bar has a length L = 12.0 cm and a uniformly distributed positive charge Q = 56.1 to. (a) With V = 0 in infinity, determine the electric potential at point P1 on the x axis, at a distance d = 2.5 cm from one of the bar ends. Suppose now that the rod has a length L = 10 cm and a linear density of charges A = cx, where c = 49.9 pClm. (b) With V = O at infinity, determine the electric potentiai at the point P2, situated on the y axis, at y = D = 3.56 cm