A distance of 1.0 meter separates the centers of

two small charged spheres. The spheres exert

gravitational force F

g and electrostatic force Fe on

each other. If the distance between the spheres’

centers is increased to 3.0 meters, the

gravitational force and electrostatic force,

respectively, may be represented as

(1) (3) 3F

g and 3Fe

(2) (4) 9Fg and 9Fe