1Q60.25 - Euler's Disk & Wobbler

The Euler's disk is very easy to use. Spin the heavy disk ( rounded edge down ) on the slightly concave base. If you listen carefully, you should hear the pitch of the spinning disk increasing as the disk slows down.
Place the "Wobbler" on a table and press down on one end with your finger. Let it slide out from under your finger and it will rotate. The figure ( X or O ) on the end that you pressed on will be stroboscopically visible.
Code Number:
1Q60.25
Demo Title:
Euler's Disk & Wobbler
Condition:
Excellent
Principle:
Conservation of Angular Momentum about Vertical Axis
Area of Study:
Mechanics

Disclaimer

Equipment:
Euler's Disk, wobbler.
Procedure:

The Euler's disk is very easy to use.  Spin the heavy disk ( rounded edge down ) on the slightly concave base.  If you listen carefully, you should hear the pitch of the spinning disk increasing as the disk slows down. 

Place the "Wobbler" on a table and press down on one end with your finger.  Let it slide out from under your finger and it will rotate.  The figure ( X or O ) on the end that you pressed on will be stroboscopically visible.  

References:
  • W. L. Andersen, "Noncalculus Treatment of Steady-State Rolling of a Thin Disk on a Horizontal Surface", TPT, Vol. 45, # 7, Oct. 2007, p. 430.
  • Russell Akridge, "Period and Amplitude", TPT, # 8, Vol. 36, p. 507, Nov. 1998. 
  • Karl C. Mamola, "A Rotational Dynamics Demonstration", TPT, # 4, Vol. 32, p. 216, April 1994.  
  • Christian Peterson, William Schwalm, "Euler's Rigid Rotators, Jacobi Elliptic Functions, and the Dzhanibekov or Tennis Racket Effect", AJP, Vol. 89, #4, April 2021, p. 349.
  • A. E. Sikkema, S. D. Steenwyk, J. W. Zwart, "Spinning Tubes: An Authentic Research Experience in a Three-Hour Laboratory", AJP, Vol. 78, # 5, p. 467, May 2010.
  • D. Petrie, J. L. Hunt, and C. G. Gray, "Does the Euler Disk Slip During its Motion?", AJP, Vol. 70, # 10, Oct. 2002, p. 1025.
  • Lorne A. Whitehead, Frank L. Curzon, "Spinning Objects on Horizontal Planes", AJP, Vol. 51, # 5, May 1983, p. 449.  
  • M. G. Olsson, "Coin Spinning On a Table", AJP, Vol. 40, # 10, p. 1543, Oct. 1972.
  • Jearl Walker, "Delights of the "Wobbler," A Coin or a Cylinder that Precesses As It Spins", The Amateur Scientist, Oct. 1982.
  • Mir Abbas Jalali, Mohammad-Reza Alam, "The Surprising Dynamics of Rolling Rings", Physics Today, Feb. 2016, p. 70.
  • Benjamin Fong Chao, "Feynman's Dining Hall Dynamics", Physics Today, Feb. 1989, p. 15.
  • "1.110, Wobbling Coins and Bottles", The Flying Circus of Physics, p. 54.
  • Don Rathjen, Paul Doherty, "Sprotating Cylinder", Square Wheels, 2002, p. 109. 
  • Neil A. Downie, " # 20, Waltzing Tube", Ink Sandwiches, Electric Worms, & 37 Other Experiments for Saturday Science", p. 171.

Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.