i am given a problem where a satellite in orbit is a certain distance from the surface of the earth. It then gives the radius of the earth. I realize i have to use the forumula: Fg=(Gm1*m2)/R^2 can i just use the distance from the surface of Earth to the satellite as R or do i add the radius of the Earth to it? And also.. anyone kind enough to give me some hints on how to solve this simple problem?? Two uniform spheres, each with mass M and radius R , touch one another. What is the magnitude of their gravitational force of attraction?