5K20.42 - Lenz's Law - Pie Tin, Water, Plate, and Magnet

Code Number:
Demo Title:
Lenz's Law - Pie Tin, Water, Plate, and Magnet
Eddy Currents, Magnetic Induction
Area of Study:
Electricity and Magnetism
Shallow Pan of Water, Pie Tin, Copper or Aluminum Plate, and Neodymium Magnet.

Place a piece of aluminum or copper plate in a pie tin, and float this in a large pan of water. A neodymium magnet brought near the plate and moved around or rotated will show the induction that the magnet produces in the plate.

  • Thomas B. Greenslade Jr., "Apparatus Named After Our Academic Ancestors, III", TPT, Vol. 52, # 6, Sept. 2014, p. 360.
  • Wojciech Dindorf,  "Lenz's Law in the Kitchen", TPT, Vol. 37, # 5, p. 268, May 1999.
  • B-287:  "Eddy Currents - Rotate Pie Pan - Nd Magnet Lift",  DICK and RAE Physics Demo Notebook.
  • Rudolf F. Graf, "Build an Eddy Current Motor", Safe and Simple Electrical Experiments, p. 68.

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