How do roller coasters do loop-the-loops?

Answer:
When roller coasters loop the loop, they are attached to the track and don't tumble off because of centripetal force. This force is the force that pushes the roller coaster against the track and also acts upon any other object that spins in a circle.
First answer by Dorkyjerk. Last edit by Dorkyjerk. Contributor trust: 31 [recommend contributor recommended]. Question popularity: 2 [recommend question].