physics question

Question

A satellite with a mass of 80kg is in a circular orbit around the Moon. The satellite is a distance of 5.0 x 105 m above the surface of the Moon. (MMOON = 7.4 x 1022 kg, RMOON = 1.7 x 106 m) a. What is the magnitude of the gravitational force exerted by the Moon on the satellite? b. What is the speed of the satellite in its orbit? c. How long does it take the satellite to complete one orbit around the Moon?

Answer 1

The satellite is basically in free fall and experiencing uniform circular motion where acceleration is v²/r.

The net force on the satellite is Fg which = mv²/r = mMG/r^2.

^{The mass if the satellite does not effect the speed of the satellite only it’s position relative to the center if mass matters (excuse the pun)}

Let 2πr/T = v.

G is a constant, r is the distance between the centers of mass of the satellite (m) and the moon (M), r is not the distance from the surface, T is the time for one orbit.

You should be able to input the given info to compute Fg, v and T.