Massive vs. Smaller Satellites: Understanding Orbiting Speeds

[rafterman]

Homework Statement

why a more massive communications satellite doesn't orbit more slowly than a smaller one?

Homework Equations

The Attempt at a Solution

The larger satellite will have more mass but it will also have a far greater gravitational force acting on it no matter where it is orbiting. These two will cancel each out. So they will freefall at the same rate providing it is the same distance from the planet.

 

[cristo]

Homework Statement

why a more massive communications satellite doesn't orbit more slowly than a smaller one?

Things to think about:
1. What type of orbit does communications satellites orbit the Earth in?
2. What force provides the acceleration for this orbit?
3. This force is the centripetal force, which can be written down for an object in circular motion.
4. Equating these two expressions should tell you the answer to your question.

 

[Chronos]

Consider Kepler's law and what role the satellite mass plays in determing the orbital period.