Amusement parks are a common attraction for many. So what is it about roller coasters that attracts people? Speed? Well hopefully not since rides in the car on the highway are at higher speeds. There is a ride however, in Europe that accelerates to 80mph in 2.3 seconds! Riders experience the negative g-force of 4.7.So why do people raise their hands up while on a ride? Well, putting your hands up stretches the trunk of one’s body and gives the internal organ more space which then exaggerates the feeling of weightlessness. Weightlessness is a feeling, not actual change in weight. When you undergo acceleration on a roller coaster, the force acting upon you is the seat which forces your body forward. Because of your body’s inertia, you feel a force in front of your body which pushes you into the seat as you feel acceleration coming from an opposing direction of the actual force. Acceleration forces get measured from a unit called g-forces, 1g is the acceleration due to gravity near the earth’s surface(9.8m/s^2). When you’re on a roller coaster acceleration constantly changes which makes the forces of gravity and acceleration connect. So while that coaster in Europe accelerates down, the upward acceleration force is greater than the downward force of gravity which makes a person feel as if they are being pulled up. While on a roller coaster you can’t feel velocity, your body can only feel the change in acceleration. The people who create roller coasters purposely create “near misses” which make you feel as though you are moving at a crazy speed and give people thrills from the quick acceleration upward and the quick acceleration downward. When a person goes through a loop on the roller coaster they undergo acceleration because of the change in speed and continuous change in direction. An increase in height leads to a decrease in kinetic energy and speed. Therefore, a ride will go through significant speeds at the bottom of the roller coaster loop and the smallest speed at the top of the loop. Your body’s inertia makes you go through an excited acceleration force as you go through the loop but also keeps a person in their seat when upside down. While it is necessary to be secured in the roller coaster, in most loops you would stay in the car regardless if you were harnessed. While moving around the loop, the net force on your body is changing and at the bottom the acceleration force is what pushes you down in the same direction as gravity. When you move up in the loop, gravity brings you into your seat while acce acceleration forces you on the floor. When you reach the top and are upside down, gravity pulls you out of the seat and down at the ground. The stronger acceleration force pushes you into your seat. Because of the 2 forces that push you in opposing directions are equivalent your body feels lighter. The more a person weighs, the more normal force they will experience they will go through while at rest. While at the top of the roller coast, you can feel weightless to some degree if the normal force become less than the your weight. Whereas, if you’re at the bottom you will feel more weight because of normal forces. Your body weight isn’t changing, it is the magnitude of the normal that is!