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body (Repaired) - Introduction A ball can be simple like a...

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Introduction: A ball can be simple, like a child’s play toy. It can be tossed to the ground in a game of jacks on a summer day. A tiny ball bearing can inhabit the inside of the wheel of a young man’s skateboard, a Christmas gift from his father. A soccer ball can threaten a goalie on a beautiful spring day as he attempts to protect his net from his opponent. In Times Square, in New York City, America welcomes a new year as a decorative ball suspended high above is lowered among the masses of people. A ball can be simple, yet it functions in many necessary and complex ways. To behold the complex, one need only look as far as the Hoover Dam or Niagara Falls where ball bearings assist in creating electricity. Dental and medical instruments such as drills use stainless steel miniature ball bearings for their corrosion resistance and precision. Computer hard drives, wind turbines and turbine engines also use ball bearings to produce spinning motion with the least amount of friction resistance. The experiment is not only about balls, but the coefficient of restitution. This is the objects amount of bounce when it strikes the ground or any other object for that matter. This is important for many materials because if a material cannot take the forces that are being applied to it then it may break or bend under these forces. Thus the material need to be tested for the coefficient of restitution which may or may not be what is wanted for the desired product. If a toy ball were to shatter in a million pieces when it bounces on the ground, the creators of this toy would have to change the coefficient of restitution because this would allow for the ball to bounce instead of break.
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Lacrosse Ball Bounce: A ball bounce is very complicated when looked at rigorously. A lacrosse ball can easily be squashed to three fourths its original diameter. Depending on the center of gravity it can be asymmetrical. “Another complicating factor is that the ball compression versus the applied force relationship is not only nonlinear but may also vary with frequency, in which case a static force versus compression curve is not particularly relevant, and dynamic curves for a spherical object are not readily available, if at all”(Cross 1). Hysteresis is a measure of the retardation of the natural tendency of rubber to return to its original shape after deformation. This retardation is caused by internal frictional forces resulting from the molecular structure of the rubber. The ball with a low coefficient of friction exhibits the greatest hysteresis. If the ball has a low hysteresis, it exhibits a more rapid return to its original form, giving it a higher bounce (“Happy and Unhappy Balls” n.p.). The dynamic hysteresis curves have been rebounded in a slighty compressed state, but the major energy loss occurs during the bounce rather than after the bounce. The experiment is limited to low speeds and on a flat surface. This will try to eliminate most of these factors or just keep them to a minimum. Coefficient of Restitution:
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body (Repaired) - Introduction A ball can be simple like a...

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