Merry-go-rounds and carousels found at amusement parks are examples of mechanisms utilizing circular motion. Curves in roads and racetracks cause automobiles and their drivers to experience it. Artificial satellites and the Moon constantly undergo circular motion in their orbits around the Earth.
Circular motion describes either an object's circular rotation or the movement of an object along the circumference, or the circular path whose points are equidistant from the circle's center. Circular motion at a fixed speed is called uniform circular motion. If the speed of the object varies, it exhibits non-uniform circular motion. A carousel operating at a constant velocity for a four- or five-minute ride is undergoing uniform circular motion, and so are the riders. As drivers in their cars slow down going into a curve and accelerate on the way out, non-uniform circular motion occurs.