posted by David .
3 There are two charges +Q and –Q/2 that locate at two positions with a separation of d as shown in Fig. 1. We
may put +Q at the origin of the x-axis to facilitate the calculation.
(a) Find the electric field for +Q and –Q/2 at the position P. (5 points)
(b) What is the total electric field at P? The answer should include the magnitude and direction of the
electric filed. (5 points)
(c) At what position(s) x is the electric field zero? (5 points)
(d) Is the field zero at any other points, not on the x axis? (5 points)