Regarding motions in Uniform Circular Motion, we need to understand the two important forces present. There is what we called a Centripetal force, this is a force that is directed towards the center around which the body is moving in a circular path. And there is also what we call a Centrifugal Force,this is an apparent(invisible) force that acts outwardly from the body that is moving in a circular path at a uniform circular motion.This centrifugal force is due to the bodies inertia..remember the law of inertia?just like when you are riding a jeepney and it suddenly stops, you are thrown towards the direction of the jeepney..same way happens to a body in a circular motion, centrifugal force pulls a body back to where it should not go...The body does not get closer to the circle because of these two forces, Centrifugal and centripetal forces which tends to balance each other and restricts the body to follow a circular path with a constant radius....Terrestrial Satellites and the science of Space Mechanics made use of this very important principle... 
3 5 3