5K20.40 - Eddy Current Levitator - Spinning Disk

Code Number:
Demo Title:
Eddy Current Levitator - Spinning Disk
Eddy Currents
Area of Study:
Electricity & Magnetism
Neodymium magnets, Round 1/4 inch thick copper plate, Pasco rotator, turntable, flexible arm.

Place the round copper plate on the rotator or turntable.  Adjust the magnet on the flexible arm so that it is toward the outer portion of the plate.  Turn on the rotator or turntable and observe the magnet rise and levitate above the plate.

  • Carlos Saraiva, "An Inexpensive Apparatus for Demonstrating Magnetic Levitation", TPT, Vol. 45, #5, May 2007, p. 311.
  • Thomas D. Rossing, John R. Hull, "Magnetic Levitation", TPT, Vol. 29, #9, Dec. 1991, p. 552.
  • Harry H. Kemp, "Lenz's Law", TPT, Vol. 15, # 9, Dec. 1977, p. 543.
  • W. M. Saslow, "Electromechanical Implications of Faraday's Law: A Problem Collection", AJP, Vol. 55, #11, Nov. 1987, p. 986.  In particular see p. 991 of this article.   
  • B-290, "Motor Disk-Levitated & Stalled", DICK and RAE Physics Demo Notebook.
  • James Luxon, "An Eddy Current Demonstration", Apparatus Notes July 1965-December 1972, p. 44.
  • James D. Livingston. "Up With Magnets!". Driving Force - The Natural Magic of Magnets. p. 157.

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