>However, this is unrelated to acceleration - these are constant angular velocities. If it were not for the force of gravity, an object in motion would move in

>However, this is unrelated to acceleration - these are constant angular velocities. If it were not for the force of gravity, an object in motion would move in the direction of its instantaneous velocity. It does not do that, it instead accelerates toward the center of the gravitational body. >In orbit this g acceleration is cancelled out by centripetal acceleration to produce 0 acceleration, or free fall. But again, they do not "cancel out," otherwise how is the instantaneous velocity constantly changing direction?