What is the minimum velocity required for a roller coaster to successfully complete a loop?

The minimum velocity required for a roller coaster to successfully complete a loop depends on factors such as the size of the loop and the gravitational force acting on the coaster. In general, the velocity must be sufficient to counteract the force of gravity and ensure that the coaster does not lose contact with the track at the top of the loop. This velocity is typically calculated using the centripetal force formula.