One of the first “roller-coaster” rides in the U.S. was actually a short coal railway in Pennsylvania that hauled coal downhill between mines and used mules to bring the empty cars back up the hill.

Roller coasters rely on two types of energy to operate: gravitational potential energy and kinetic energy. Gravitational potential energy is the energy an object has stored because of its mass and its ...

This article was taken from the November 2014 issue of WIRED magazine. Be the first to read WIRED's articles in print before they're posted online, and get your hands on loads of additional content by ...