Four charges are placed on the corners of a square that lies in the first quadrant of the x-y plane with sides of length 3m. One corner of the square is on the origin of the coordinate system. A charge Q1=5uC is at the origin. A second charge Q2=6uC is at the other corner lying on the x-axis. A third charge (Q3=9uC) is lying on the corner on the y-axis and the final corner has a charge of -7uC lying on it. Assume that the charge are fixed at these points and dont move.
A) What is the electric field ( magnitude and direction) at the origin ignoring the 5uC charge?
B) What is the electric potiental at the origin again ignoing the 5uC charge there?
C) Find the force (magntude and direction) on the charge at the origin?