 Wysłany: Pon 6:09, 03 Sty 2011 Temat postu: New Balance What Are The Forces Acting On A Roller |
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eleration forces are measured in so-called "g forces," where 1 g is the force of acceleration due to gravity near the surface of the earth, which is 9.8 meters per second squared, or 32.2 feet per second squared. A roller coaster's acceleration is constantly changing, as is its position relative to the ground, and that causes the acceleration and the gravity forces to interact in unusual ways. When you are coasting down a steep hill at a high rate of speed, gravity pulls you downward, while acceleration seems to be pulling you upward. At a certain acceleration rate,Nike Dunk, the forces cancel each other out, and this is when you feel weightless - just like a skydiver in free fall. When riding a coaster,Nike Free 5.0 Shoes, you are continuously changing your direction of motion when you go through a loop. Not only is there acceleration,Jordan AJF6, but the direction and magnitude of the acceleration is always changing. In a couple of seconds you could feel accelerations of 2 g downward to 3 g upwards. This is what happens when you move to the top of the loop to the bottom of the loop. Those accelerations are what produce the "thrill" in thrill rides. Some scientists and doctors think that excessive g forces may be dangerous to the human body, particularly the brain. The state of New Jersey has enacted laws limiting g forces, and similar legislation has been proposed on a federal level. However, research scientists at the University of Pennsylvania have concluded that roller coasters do not produce g forces large enough to harm riders' brains. The biggest risk of g forces is loss of consciousness because blood pools in limbs and away from the brain. But this effect requires sustained high g forces over three-quarters of a minute. The high g forces on roller coasters usually only last two or three seconds. 相关的主题文章： Nike Air Max LTD Alabama Ballet At Gorham’s Bluff Nike Dunk Shoes Budget Filmmaking - 4 Secrets To Making A Great Film With A Low Nike Air Max 95 The Battle Of Trafalgar By Steven Dews |
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