There is no such animal as centrifugal force. It is fictional. Any object in motion will tend to remain in motion in a line determined by the vector of the force that set it in motion. This is Newton's First Law, and the following is from Wikipedia:
"This is known as uniform motion. An object continues to do whatever it happens to be doing unless a force is exerted upon it. If it is at rest, it continues in a state of rest. If an object is moving, it continues to move without turning or changing its speed. This is evident in space probes that continually move in outer space. Changes in motion must be imposed against the tendency of an object to retain its state of motion. In the absence of net forces, a moving object tends to move along a straight line path indefinitely." (Let me add here that this is true in the absence of gravity and friction.)
To keep an object in circular orbit, one must apply a force directed inward toward the center of the orbit. This force vector is centri-petal, "center-seeking". Think of a sling shot. Before release, the stone travels in a circle because the sling allows you to apply a centripetal force. The moment you let go of the sling, the stone flies off in a line tangential to the radius of its orbit, because that's the direction of the force vector that motivates it. If there really were any such thing as "centrifugal" force (center-fleeing), then the stone would fly away in a line parallel to the radius of the orbit. That does not happen. If David had not understood this, Philistines would rule. He would have missed Goliath by a mile.
