1912 marks the year John Miller designed the first Under friction roller coaster
these colossal, twisted structures provide an exhilarating and frenetic ride. They wed technology to basic and seemingly incompatible emotions, such as panic, courage, fear, joy, vertigo, and amusement. Built as if to exclusively prove Newton's theories, the science of roller coasters abounds with all his terminology: acceleration, mass, gravity, movement, and inertia. But in all this, what is really thrilling is the free fall, the attraction of the abyss.
Safety Details The designers of these extreme machines take into account all possible safety factors to provide as safe an experience as possible. Riders are made to wear safety belts, and machine parts are inspected on a regular basis to prevent accidents. Joints and beams are X-rayed for flaws. Safety devices applied to the drive chain before cars reach the top prevent the train of cars from moving backward. These devices are also installed on some of the hills, where the train slows down in its climb. In the event of wind gusts and sudden decelerations, these preventive measures keep the train in place and stop it from backtracking
Wheels to keep the trolley on the track Three types of wheels are needed: upper wheels to control the train for most of the route; lower ones for use on the hills—G forces are sometimes greater than the weight of the train; and lateral wheels to prevent the train from derailing on curves..
Force ofGravity in Action Most of the motion in a roller-coaster ride is a response to the Earth's gravitational pull. No engines are mounted on the cars. After the train reaches the top of the first slope—the highest point on the ride— the train rolls downhill and gains speed under the Earth's gravitational pull. The speed is sufficient for it to climb over the next hill. This process occurs over and over again until all the train's energy has been lost to friction and the train of cars slows to a stop. If no energy were lost to friction, the train would be able to keep running as long as no point on the track was higher than the first peak.
1-POTENTIALENERGY When the wagon reaches the highest point of the roller coaster, it has a great deal of potential energy.
2-MECHANICALENERGY At a certain point in the trajectory, both energies (potential and kinetic) cancel each other out
3-KINETIC ENERGY is energy of motion that is, the energy released by the train every time it descends.