5H20.20 - Levitating Magnetic Disks

Code Number:
5H20.20
Demo Title:
Levitating Magnetic Disks
Condition:
Excellent
Principle:
Magnetic Fields Around Permanent Magnets
Area of Study:
Electricity & Magnetism

Disclaimer

Equipment:
Radio Shack magnetic disks, Plexiglas rod stands.
Procedure:

Place the magnets on the support rod with like poles facing each other (repulsion or repelling).  Notice that as more magnets are placed on the rod the magnets are squeezed closer together due to the weight (pressure).

References:
  • Herbert Looser, "Effective Dipole Position of Magnets", TPT, Vol. 46, # 1, Jan. 2008, p. 4.
  • Martin Connors, Farook Al-Shamall, "Authors Response to 'Herbert Looser, "Effective Dipole Position of Magnets", TPT, Vol. 46, # 1, Jan. 2008, p. 4.
  • Martin Connors, Farook Al-Shamali, "The Magnetic Torque Oscillator and the Magnetic Piston", TPT, Vol. 45 # 7, Oct. 2007, p. 440.
  • Ron Singleton, Dallas Trinkle, Terrence Toepker,  "Amazing Magnetic Moments",  TPT, Vol. 35, # 2, p. 122, Feb. 1997. 
  • John D. McGervey,  "Hands-on Physics for Less Than a Dollar Per Hand",  TPT, Vol. 33, # 4, p. 238, April 1995.
  • William Lonc,  "Novel Third-Law Demonstration",  TPT, Vol. 33, # 2, p. 84, Feb. 1995.
  • Herbert H. Gottlieb, "Ceramic Magnets",  TPT, Vol. 14, # 3, p. 181, March 1976, reprinted in TPT, Vol. 41, # 3, p.  186, March 2003.
  • S. Defrancesco and V. Zanetti, "Experiments on Magnetic Repulsion", AJP, Vol. 51, #11, Nov. 1983, p. 1023.
  • Er-11:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • B-060:  "Coupled Oscillating Magnets",  DICK and RAE Physics Demo Notebook.
  • Tik Liem,  "The Floating Discs",  Investigation to Science Inquiry,  p. 224.
  • Martin C. Sagendorf, "Stacked Magnets", Physics Demonstration Apparatus, 2009, p. 57.
  • Jodi and Roy McCullough, "Magnetism with Floating Magnets", The Role of Toys in Teaching Physics", p. 3.28.
  • Janice VanCleave, "55, Floating Magnets", Teaching the Fun of Physics, p. 89.
  • Janice VanCleave,  "Glider",  201 Awesome, Magical, Bizarre, & Incredible Experiments,  p. 106.
  • Janice VanCleave, "19, Pushing and Pulling", Magnets, p. 76.

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.