A +14 nC charge is fixed at (0 cm,0 cm), and a non-fixed particle of mass 2 g and charge -3 nC is placed at x = (6 cm, 0 cm).   (a)  At what position would a -27 nC have to be fixed so that the net electric force on the 2-g particle is zero? (b)  What is the value of the -27 nC particle’s electric field at the position of the 2-g particle for the case described in Part (a)? (c)  If that same -27 nC were formed into a spherical shell of radius 1 cm, where would the center of the sphere need to be placed to have the same electric field calculated in Part (b)? (d)  If, instead, that same -27 nC were spread evenly over a square, non-conducting thin plane – placed close enough to the 2-g particle so that it is effectively very large – what would the side length of the plane need to be to create the same electric field calculated in Part (b)?

A +14 nC charge is fixed at (0 cm,0 cm), and a non-fixed particle of mass 2 g and charge -3 nC is placed at x = (6 cm, 0 cm).  
(a)  At what position would a -27 nC have to be fixed so that the net electric force on the 2-g particle is zero?
(b)  What is the value of the -27 nC particle’s electric field at the position of the 2-g particle for the case described in Part (a)?
(c)  If that same -27 nC were formed into a spherical shell of radius 1 cm, where would the center of the sphere need to be placed to have the same electric field calculated in Part (b)?
(d)  If, instead, that same -27 nC were spread evenly over a square, non-conducting thin plane – placed close enough to the 2-g particle so that it is effectively very large – what would the side length of the plane need to be to create the same electric field calculated in Part (b)?