5G10.11 - Refrigerator Magnets & Floppy Disks

Code Number:
Demo Title:
Refrigerator Magnets & Floppy Disks
Magnetic Forces & Fields
Area of Study:
Electricity & Magnetism
Flat pad type refrigerator magnets, fine iron filings.

Place the magnets under a piece of paper and shake on a fine coating of the iron filings.  The iron filings should line up in rows signifying the rows of North/South poles on the flat magnets.  In other words these magnets are made with alternating lines of North and South poles.

  • Stephen Kanim and John R. Thompson, "Magnetic Field Viewing Cards", TPT, Vol. 43, # 6, p. 355, Sept. 2005.
  • Ena S. Bichsel, Brenda Wilson, and Wilhelmus J. Geerts,  "Magnetic Domains of Floppy Disks and Phone Cards Using Toner Fluid",  TPT, Vol. 40, # 3, p. 150, March 2002.
  • Martin F. Schmidt, Jr.,  "Investigating Refrigerator Magnets",  TPT, Vol. 38, # 4, p. 248, April 2000.
  • H. Richard Crane,  "How Things Work - A Thermometer Whose Memory Is a One-Sided Magnet",  TPT, Vol. 37, # 3, p. 148, March 1999.
  • Daniel Lottis, Christopher Baker, and Heather Pounds,  "Giant Magnetoresistance Sensors",  TPT, Vol. 36, # 4, p. 216, April 1998.
  • David G. Haase, "The Mysterious Magnets", TPT, Vol. 34, # 1, p. 60, 1996.
  • "Refrigerator Magnets", Physics From the Junk Drawer, 3rd Edition, The Science House, North Carolina State University, p. 39.

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