A charge is to be placed at the empty corner to make the net force at corner A point along the vertical direction. What charge (magnitude and algebraic sign) must be placed at the empty corner if the three charges have the same charge of +8.45 μC?
Force = kq1q1/r^2
where k = 8.99 x 10^6
So we know that the horizontal charges must cancel out since the net force is vertical..ok..so we know there is a downwards vertical force on A coming from the top right charge, a leftwards horizontal charge from A coming from the bottom right charge...I know the unknown charge on A (at an angle of 14 degrees [tan theta = d/4d]) will be diagonal...not too sure where to go from here!! Any help would be appreciated!!