Roller Coaster at different positions A roller coaster is a machine that uses gravity and inertia to send a train of cars along a winding track. This combination of gravity and inertia, along with G-forces and centripetal acceleration give the body certain sensations as the coaster moves up, down, and around the track.

A roller coaster is moved only by the forces of inertia and gravity, for most of its travel. The only exertion of energy occurs at the very beginning of the ride, when the coaster train is pulled up the first hill (called the lift hill) with a chain and motor (or other mechanical device) exerting a force on the train of cars. Once the cars are lifted to the top of the hill, gravity takes over and the remainder of the ride is an experience of the physics of energy transformation.

The purpose of keeping the coaster train at the top of the hill is to build up a sort of reservoir of potential energy. Potential energy–the energy of vertical position–is dependent upon the mass of the object and the height of the object. As the coaster train gets higher in the air, there is a greater distance at which the gravity can pull it down. As the coaster train start cruising down that first hill, gravity takes over and this potential energy will be released as kinetic energy––the energy of motion that takes you down the hill.

People are strapped to ensure safety Many safety systems are implemented in roller coasters. Persons in roller coaster are strapped properly to overcome the risk with this huge machine.

Smoothening ring the tracks would only possibly avoid the jerks of the roller coaster and will make the ride less jerky. This Smoothening wouldn't reduce the acceleration needed to turn. The faster the train moves, the faster everything must accelerate as the track bends.

Doubling the speed of the roller coaster would double the changes in velocity associated with each bend and hence it would halve the time required for that velocity to change.

Thus, doubling the roller coaster's speed would quadruple the accelerations it experiences on the same track and thus will quadruple the forces involved during the ride. A roller coaster ride already involves some pretty intense forces and accelerations. If those forces and accelerations were increased by a factor of 4, they would be more than most people could handle.

Thus I wouldn't expect many riders on a double–speed bullet train roller coaster.

Lower and Higher tracks of Roller Coster Ride design with higher and lower tracks is crucial for increasing excitement. In the ride operations menu, making the ride time longer (by increasing the number of swings, turns, the time limit etc) increases the excitement rating.

From that point on, the roller coaster does two things with its energy. First, it begins to transform that energy from one form to another––from gravitational potential energy to kinetic energy and from kinetic energy to gravitational potential energy, back and forth.

Second, it begins to transfer some of its energy to its environment, mostly in the form of heat and sound. Each time the roller coaster goes downhill, its gravitational potential energy decreases and its kinetic energy increases. Each time the roller coaster goes uphill, its kinetic energy decreases and its gravitational potential energy increases. But each transfer of energy isn't complete because some of the energy is lost to heat and sound.

Because of this lost energy, the roller coaster can't return to its original height after coasting down hill. That's why each successive hill must be lower than the previous hill.

Eventually the roller coaster has lost so much of its original total energy that the ride must end. With so little total energy left, the roller coaster can't have much gravitational potential energy and must be much lower than the top of the first hill.