|Serway, Raymond A., Faughn, Jerry S., Moes, Clement J. College Physics Sixth Edition. Pacific Grove, California: Thomson Learning. 2003.||"Assume the speed of the roller coaster is 12.0 m/s at the top of the loop, which has radius 8.00 m. Find the force exerted by the seat on a 70.0 kg passenger. Then assume the speed remains the same at the bottom of the path and find the force exerted by the seat on the passenger at this point."||top of loop 0.8 g
bottom of loop 2.8 g
|Acceleration Stress. Encyclopedia Britannica. 1999.||"Entry may create a heavy force on the riders as high as 5 g, but only for a few seconds—any longer and riders may blackout from acceleration stress…. Often the designer will adjust the radius at the top of the loop to create a centripetal force of 2 g, allowing the riders, after subtracting the value of gravitation (1 g), to experience normal weight levels while upside down."||top of loop 2.0 g
bottom of loop 5.0 g
|Taylor, Richard L. CBL Measurements at Six Flags Over Texas.The Hockaday School, Dallas, Texas. June 2006.||min. 0.9 g
max. 5.0 g
|Homer. Revolution. Six Flags Magic Mountain. Valencia, California. June 2006.||"Acceleration: Positive G's 4.9 G's"||max. 4.9 g|
As a rider starts the descent down the first drop of a roller coaster, she begins a one-minute adventure filled with various sensations of weightlessness, heaviness, and jerkiness. G-forces explain the various sensations experienced on a roller coaster loop (1 g = 9.8 m/s2).
A person who feels weightless has not lost weight. The force of gravity acting upon the person is the same magnitude as it always. The normal force however has a small magnitude at the top of the loop (where the rider often feels weightless) and a large magnitude at the bottom of the loop (where the rider often feels heavy). Most roller coasters have acceleration between 2 g and 5 g. At the top of the loop, the gravity force is directed inward and thus, there is no need for a large normal force in order to sustain the circular motion. The formula for centripetal acceleration ac = v2/r was used to determine the top and bottom acceleration of a ride. After entering the values, the top and bottom g-forces were determined 0.8 g and 2.8 g.
A rider feels heavy at the bottom of the loop because of the large force (five times her weight) exerted by the seat upon her body. Batman and Robin: The Chiller, Shockwave and Magic Mountain rides at Six Flags respectively have a maximum acceleration of 5.0 g, 5.0 g, and 4.9 g. In actuality, she is not heavier; she is only experiencing the large magnitude of force that is normally exerted by seats upon people while at rest.
Saintedym Wills -- 2006