The charges and coordinates of two charged particles held fixed in the xy plane are: q1=2.90 ?C, x1=3.900 cm, y1=8.700 cm, and q2=1.80 ?C, x2=8.879 cm, y2=13.183 cm, Find the magnitude and direction of the electrostatic force on q2.
What are the x and y coordinates of a third charge q3=3.00 ?C, if the net electrostatic force on q2 is zero?