posted by Chris .
A communications satellite with a mass of 400 is in a circular orbit about the Earth. The radius of the orbit is 3.7×104 as measured from the center of the Earth.
Calculate the gravitational force exerted on the satellite by the Earth when it is in orbit.
The Law of Universal Gravitation states that each particle of matter attracts every other particle of matter with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Expressed mathematically,
F = GM(m)/r^2
where F is the force with which either of the particles attracts the other, M and m are the masses of two particles separated by a distance r, and G is the Universal Gravitational Constant. The product of G and, lets say, the mass of the earth, M, is sometimes referred to as GM or µ (the greek letter pronounced meuw as opposed to meow), the earth's gravitational constant.