1D55.10 - Central Forces - Broken Ring

Code Number:
Demo Title:
Central Forces - Broken Ring
Forces Due To Circular Motion
Area of Study:
3/4 Arc Steel and Plastic Rings and 1" Ball Bearings.

Set the arc on the table or overhead projector. Roll the ball bearing against the inside of the arc. When the ball bearing reaches the end of the arc it will exit and roll in a straight line.

  • Harry Rheam,  "Centripetal Force on an Overhead Projector",  TPT, Vol. 33, # 3, p. 182, March 1995.
  • Jonathan Mitschele, "A New Use for an Old Pickle Bucket", TPT, Vol. 32, # 4, Apr. 1994, p. 252.
  • "The Orange Wave", Physics Today, Dec. 2014, p. 96.
  • Borislaw Bilash II, David Maiullo, "I'm Going in a Straight Line", A Demo a Day: A Year of Physics Demonstrations, p. 128.
  • Robert Ehrlich,  "The Missing Circular Arc",  Why Toast Lands Jelly-Side Down, p.  22- 23.
  • James Cunningham and Norman Herr,  "Newton's First Law",  Hands-On Physics Activities with Real-Life Applications, p.  58, 67.
  • Borislaw Bilash II, “The Path of a Marble“, A Demo A Day – A Year of Physical Science Demonstrations, p. 231.

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