00:01
All right, so let's say we're looking at newton's law of gravity, which says that, you know, the force between two masses separated by a certain distance are.
00:08
If this is our larger mass, this is our smaller mass, m, this distance is r, then it's given by this.
00:14
So the centripetal force, given about this object in orbit, moving at a speed v, is going to be supplied by the gravitational force.
00:24
And so the mass of the smaller orbiting object is going to cancel.
00:28
And we'll get v squared equals the square root, or sorry, v squared equals gm over r, and therefore our orbital velocity is the square root of g times m over r.
00:42
So that's part a, just to prove that.
00:46
Part b, we want to find the height above earth's surface for a geosynchronous satellite...