College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 60

Three equal positive charges are at the corners of an equilateral triangle of side a as in Figure P15.34. Assume the three charges together create an electric field. (a) Sketch the electric field lines in the plane of the charges. (b) Find the location of one point (other than) where the electric field is zero. What are (c) the magnitude and (d) the direction of the electric field at P due to the two charges at the base