Posted by mo on .
a point charge q1= 4.00nC is at a point (0.6,0.8) in the xy axis, and a second point charge q2=4.73nC is at the point (0.6,0), calculate the magnitude and direction of the net electric field at the origin due to these two points.
Ive tried calculating the two separate electric fields and adding them up, but i just don't know which to make positive or negative. is using E=k*(q/r^2) even the correct equation for this type of problem?

physics 
Anonymous,
ys