Final answer:
Amusement park rides like Ferris wheels and vertical loops exhibit forces such as gravity, normal force, and tension which affect their motion. Riders experience centripetal force in circular motions, and the direction and magnitude of these forces influence the ride's safety and functioning.
Step-by-step explanation:
When a Ferris wheel is loaded with people at various positions such as 4 o'clock, 1 o'clock, 9 o'clock, and 6 o'clock, and begins to turn, several forces are acting on the system. The most significant forces include gravity, normal force from the seat, and tension in the supporting structures. Gravity affects the angular momentum and angular velocity by exerting a torque whenever the center of mass is not aligned vertically with the axis of rotation. For riders in a Viking ship ride shaped like a pendulum, at the top of their swing, they experience a momentary stillness due to gravity pulling them down, creating a pendulum-like motion. When rides make vertical loops, if the car is at the right speed, gravity provides the necessary centripetal force to make the loop. However, if the car goes faster than this speed, an additional normal force from the track pushes on the car to supply the necessary centripetal force, which acts inward toward the center of the loop. If the car goes slower, the normal force decreases, and the safety restraints ensure the riders remain in the car.
In the scenario of amusement park rides like a large vertical barrel, the riders are pinned to the wall as the barrel spins; this effect is due to the centripetal force necessary to keep the riders in circular motion. The real force that pins the riders to the wall in an inertial frame of reference is the normal force exercised by the wall on the riders.