Skating and Angular Momentum *
*Note: This is an abbreviated Project Idea, without notes to start your background research, a specific list of materials, or a procedure for how to do the experiment. You can identify abbreviated Project Ideas by the asterisk at the end of the title. If you want a Project Idea with full instructions, please pick one without an asterisk.
Abstract
Place a desk chair (one that rotates easily on ball bearings) in the center of the room, away from any obstructions. Put your hands on your lap and have a helper give you a push to start you rotating. You'll need to quantify the results somehow. For example, your helper could measure the number of revolutions you make in 5 seconds. Now try extending your arms after your helper starts you spinning. Next, start with your arms out, and bring them in close to your body after you start spinning. You can also try this while holding a heavy weight in each hand. Repeat each trial at least three times (take breaks so you don't get too dizzy!) Advanced: try to use the conservation law (angular momentum) to write an equation to predict how fast you should spin in each condition. How well does your prediction agree with your actual results? Try to explain any deviations between predicted and actual results. If you need help, you can use Science Buddies Ask an Expert Forum to check the derivation of your equation. (Idea from: Goodstein, 1999, 114-116.)Share your story with Science Buddies!
Last edit date: 2013-01-10
Bibliography
Goodstein, M., 1999. Sports Science Projects: The Physics of Balls in Motion. Berkeley Heights, NJ: Enslow Publishers.Share your story with Science Buddies!
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