a body with uniform motion at surface of earth would revolve around the earth. is it true that if the velocity of the body is sufficiently low than it would not revolve and fall to ground? can we determine the velocity is it is so? So is it true that the moon, on the grounds that moon was not a part of earth, was travelling in uniform motion before it came to earth's field and started to revolve? And if had it not been in uniform motion, would collide with the earth?