Newton's Laws Of Motion Practice Test

Centripetal force is not a separate, new force. It is the net inward pull toward the center that keeps an object moving in a circle, arising from real forces such as tension, gravity, or friction. The inward components of these real forces add up to provide the centripetal effect, with magnitude m v^2 / r, directed toward the center. So the best description is that the centripetal force is the net inward component of real forces toward the center. This isn’t a distinct force of its own, and it isn’t caused by a centrifugal force (which is a fictitious force that appears only in rotating frames). It also isn’t always equal to gravity alone—gravity can provide the inward pull in some cases, but other forces can contribute as well, or gravity may be absent, depending on the situation.