Roller Coaster Wheels

Most recent answer: 06/07/2016

What kind of wheels/connecting system does a roller coaster use when it is traveling vertically? Obviously not normal wheels, because it would fall off. Please help!
- Chloe W. (age 19)
Chicago, Illinois, USA

The key to how roller coasters work is not that they have special wheels holding them to the track. It's that as they move quickly along the curved track, their velocity direction is changing due to that curvature. That means they're accelerating. If the acceleration is bigger than the gravitational acceleration, then something other than gravity must be pushing on them. It's the force from the tracks, which then must be in contact with the wheels. A roller coaster in the same position but moving too slowly wouldn't be accelerating as much and would fall off.

Mike W.

(published on 06/07/2016)