1D50.20 - Whirligig/Twirling Weights

Code Number:
1D50.20
Demo Title:
Whirligig/Twirling Weights
Condition:
Good
Principle:
Conservation of Angular Momentum
Area of Study:
Mechanics
Equipment:
String through tube with 2 unequal masses, additional masses.
Procedure:

The two masses on a string when once started whirling is most safely stopped by pulling back down on the large weight.

References:
  • Paul Hewitt, "Answer to January 2019 Figuring Physics", TPT, Vol. 57, #2, Feb. 2019, p. 116.
  • Richard D. Kaufman, "Angular Acceleration Without Torque?", TPT, Vol. 50, #1, Jan. 2012, p. 35.
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  • Jeff Whittaker, "Demonstrating Circular Motion With a Model Satellite/ Earth System", TPT, Vol. 46, #4, Apr. 2008, p. 237.
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  • Robert Johns, "Acceleration Without Force?", TPT, Vol. 41, #3, Mar. 2003, p. 156.
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  • Mm-1, 2, Ms-5: Freier and Anderson, A Demonstration Handbook for Physics.
  • M-198: "Three Neons & Ball on a String", DICK and RAE Physics Demo Notebook.
  • M-742: "Ball on String-Coin in Balloon", DICK and RAE Physics Demo Notebook.
  • Tik Liem, "A Measure of Centripetal Force", Investigation to Science Inquiry, 14.18, 380.
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  • "16. In and Out", Janice VanCleave's 201 Awesome, Magical, Bizarre, & Incredible Experiments. 
  • "32. In and Out", Janice VanCleave's Astronomy for Every Kid: 101 Easy Experiments That Really Work, p. 70.
  • "Concepts in Motion", "E12: Centripetal Force", The Project Physics Course - Teachers Resource Book, p. 84.
  • Robert Ehrlich, "Whirligig with a Hanging Weight", Turning the World Inside Out, p. 72 - 73.
  • Charels Windsor, "Measuring the Acceleration of Gravity with a Rotating Rubber Stopper", Ames High School Notes.
  • "Lift the Pot", The Usborne Book of Experiments.
  • Borislaw Bilash II, “Centripetal Force and Acceleration“, A Demo A Day – A Year of Physical Science Demonstrations, p. 216.


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