[问答题]
Determine the direction and magx*aww*ly *b2a nitud2a0sm:z 7rn ;-vqwe cte of the electric field at the point P shown in Fig. 16–59. The two charges are separated by a distance of 2a. Poinr vweqm7ca2 ;- :zsnt0t P is on the perpendicular bisector of the line joining the charges, a distance x from the midpoint between them. Express your answers in terms of Q, x, a, and k.
