Amusement parks have been around for decades and they are just as popular as they have ever been. For the most part, the physics and theories used to build these wonderful theme parks in the early years have withheld the test of time and are still exactly the same. Most people don't stop to think about how many amusement parks really rely on physics. If these thrilling rides were just constructed like you might build a tree house and physics was never applied, then the millions of people that flock to these attractions each year would simply have to find something else to waist their money and adrenaline on.
First, we will look at the roller coaster. This is possibly one of the main attractions at an amusement park. What many people don't recognize is the fact that roller coasters aren't propelled by an engine. There is a good reason to back up the fact that the first hill is always the highest. Once the coaster is pulled up the hill by the crank, potential energy is at its fullest. As the coaster is making its way down the hill, that potential energy is converted into kinetic energy. At the bottom of the hill, kinetic energy is at its highest. Throughout the rest of the ride, the coaster is simply propelled by the constant conversion from potential to kinetic energy and back again. Another factor that enters into the extreme speeds that roller coaster can reach are the wheels. There are basically three types of wheels. The running wheels keep the coaster on its path along the rails. The friction wheels help to control the side to side movement of the coaster. And, the last set of wheels helps the coaster stay planted on the rails of the track, even when inverted. The car is eventually stopped by a compressed air braking system. (Amusement Park Physics)
The carousel is one of the most traditional theme park rides. At first glance, the carousel may look as though it's only a simple, graceful wheel of steel. It actually depends highly on a specific combination of certain motions and forces. Each of the seats has to complete a complete circle in exactly the same period. Eventually, the seats on the outside of the carousel will travel a farther distance than those closer to the hub; because of this, the outside seats will move at a faster linear speed than the seats on the inside. (Amusement Park Physics)
Another popular ride at the amusement parks is the bumper cars. Even they use physics to make them fun. First of all, the cars are designed so that when they collide, the rider will not sustain any damage. This is done with the thick rubber bumper used to absorb the shock from the other cars. The cars are usually powered by and electric engine, though gas engines can power them. A pole runs from the back of the car to the ceiling, which contains the electricity. The metal wheels on top of the pole harness electricity. The engine is therefore powered by that electrical current which creates kinetic energy, though some of the energy is lost through friction and heat. The reason that the drivers feel either a sharp or not so sharp change in their motion is due to Newton's Third Law of Motion, Inertia, and the mass of the driver and car. Newton's third law says that when car #1 hits car #2, car #2 will exert an equal an opposite force onto car #1. Inertia comes into play because an object in motion will stay in motion in a straight line unless otherwise acted upon; this is why seat belts are needed, so that the driver stays in the car. The mass should be taken into consideration also; a person with more mass will experience the greater jolt. More mass will have a greater change in motion. (Amusement Park Physics)
Rides that imitate playground swings are actually classified as pendulums. As the swing or ride reaches the highest point in its flight, the rider often experiences weightlessness. This feeling is even more drastic if the ride travels in a 360-degree circle. While it may be thought to be true by the rider, the forces of gravity are not overcome at the moment of "weightlessness". What is actually happening is that the force of the seat or swing is pushing up on the rider with enough magnitude to counterbalance the forces of gravity. At the top of the circle, the rider may often fall out of their seat. At this point the rider is not in complete contact with the seat and the seat is no longer applying the force upward, thus awarding the rider with a weightless sensation (the force that the seat applies is equal to the force the rider applies to the seat). Pendulum rides often give out higher g-forces than other amusement park rides. This is due to centripetal force. Centripetal forces are the forces that tend to push the object to the center of the circle; and they occur when an object is traveling in a circular motion. Gravity is always pushing down upon the rider; therefore something else must apply the centripetal force. The seat applies the centripetal force. The "g" rating depends on the amount of force applied by the seat. If the force is thrice the person's weight, then the person is experiencing 3 g's (the force applied by the seat is three times the force of gravity). (Amusement Park Physics) (Open Park Physics)
Yet another concept of amusement park physics is that of free-fall. Rides that fall under the free-fall category are usually made up of three processes. First, a set force, depending on the weight of the cart and the estimated weight of the passengers, is applied in order to pull the elevator to the top of where it will be dropped. From there, the elevator is momentarily suspended above the ground. The last part is the proverbial plunge into the abyss. The force applied in order to get the elevator to the ground is strictly gravity. The cart will accelerate at the same rate, 9.8m/s/s, regardless of the mass of the riders. If the elevator were allowed to simply hit the ground, it would be crushed. In order to get around this devastating event, ride builders use an exit track, which curves away from the original straight track. (Open Park Physics)
In conclusion, physics is a big factor in amusement parks. In fact, physics is responsible for the fact that generally speaking, there are very few ride-related injuries at amusement parks each year. According to the National Consumer Product Safety Commission, 270 million people attend theme parks each year, and only 7,000 become injured (0.00259%) (Amusement Park Physics). And even most of this can be prevented. Most injuries are due to the lack of maintenance, and the ignoring of the safety rules. So, usually you don't have to think twice about your safety when getting on a ride. The only thing you have to concern yourself with is having fun!