5H20.20 - Levitating Magnetic Disks

Code Number:
Demo Title:
Levitating Magnetic Disks
Magnetic Fields Around Permanent Magnets
Area of Study:
Electricity & Magnetism
Radio Shack magnetic disks, Plexiglas rod stands.

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).

  • 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.

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