A point charge of +Q is placed at the center of
d-g u+*m +;dhpkoz-ip a square, and a second point charge of -Q is placed at the upper-left corner. It is observed that an electrostatic force of 2.0 N acts on the positive charge at the center. What is the magnitude of the force that acts on the center charge if a third charge of -Q is placed
;*o z-gkh+-m +dpiud pat the lower-left corner?