5A10.20 - Electrophorus

Code Number:
Demo Title:
Area of Study:
Electricity & Magnetism
Electrophorus Plate, Charging Plate, Silk, and Cats Fur.

Charge the electrophorus plate by rubbing it with the cats fur. This plate will have a positive charge when this is done. Set the charging plate onto the electrophorus and draw a spark off the back of the plate with your finger. Remove the charging plate from the electrophorus and you should now have a negative charge. The electrophorus should stay charged for several cycles of the charging and discharging operation.

The film canisters contain a neon light that will flash in the presence of an electrostatic field.

  • Robert A. Morse, "Simple Pencil-and-Paper Notation for Representing Electrical Charge States", The Physics Teacher, November 2017, volume 55, pg. 470. 
  • David R. Lapp, "Bigger Cap... Bigger Spark", TPT, Vol. 30, # 8, Nov. 1992, p. 454.
  • William R. Gregg, "Three Inexpensive High-Voltage Electricity Demonstrations", TPT, Vol. 30, # 7, Oct. 1992, p. 400 - 401. 
  • William Layton,  "A Different Light on an Old Electrostatics Demonstration",  TPT, Vol. 29, # 1, p. 50, Jan. 1991.
  • R. A. Morse, "The Automatic Electrophorous", TPT, Vol. 29, # 4, Apr. 1991, p. 225.
  • R. D. Edge, "Electrostatics With Soft-Drink Cans", TPT, Vol. 22, # 6, Sept. 1984, p. 396 - 398.
  • Donald S. Ainslie, "Can an Electrophorus Lose Its Charge and then Recharge Itself ?", TPT, Vol. 20, # 4, Apr. 1982, p. 254.
  • Donald S. Ainslie, "Inversion of Electrostatic Charges in a Cylindrical Electrophorus", TPT, Vol. 18, # 7, Oct. 1980, p. 530.
  • Oleg Jefimenko, David Walker, "Electrets", TPT, Vol. 18, # 9, Dec. 1980, p. 651.
  • John E. Girard, "Negative Charges from an Electrophorus", TPT, Vol. 16, # 6, Sept. 1978, p. 402.
  • John W. Layman and Delbert J. Rutledge, "Neon Lamps and Static Electricity", TPT, Vol. 10, # 1, Jan. 1972, p. 49.
  • Thomas B. Greenslade, Jr., "Electrophorus" (Photo), AJP, Vol. 79, # 1, Jan. 2011, p. 102.
  • D. S. Ainslie, "What are the Essential Conditions for Electrification by Rubbing?", AJP, Vol. 35, # 6, June 1967, p. 535.
  • Ea-19:  Freier and Anderson,  A Demo Handbook for Physics.
  • E-140:  "Electrophorus",  DICK and RAE Physics Demo Notebook.
  • E-10:  Richard Manliffe Sutton, Demonstration Experiments in Physics.
  • Tik Liem, "The Spark - Producing Finger", Investigation to Science Inquiry, p. 246.
  • Robert A. Morse, "Laboratory Activity 6: Neon Bulbs and Motion of Charge", Teaching about Electrostatics, p. 3 - 17.
  • Robert A. Morse, "Laboratory Activity 3: The Electrophorus and Charging by Induction", Teaching about Electrostatics, p. 3 - 9.
  • George M. Hopkins, "Frictional Electricity", Experimental Science, p. 368.
  • John Henry Pepper, "Electrophorus", Cyclopadic Science Simplified, p. 245.
  • Carson I. A. Ritchie, "Electrophorus", Making Scientific Toys, p. 149.
  • Pat Murphy, Ellen Macaulay, and the staff of the Exploratorium, "Super Sparker - The Electrophorus", Exploratopia, p. 327.
  • David Kutliroff, "77, The Electrophorus - An Ancient Charging Device", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 169.
  • "Charge and Carry", Science Snackbook, p. 20.1 - 20.3.
  • Robert DeSerio, "Electrostatics - Lab Experiment", Dept. of Physics, Univ. of Florida, 2012.
  • Grant Mellor, "Tiny Shocks", Flying Tinsel, 1993, p. 33 - 37.
  • Grant Mellor, "A Second Look", Flying Tinsel, 1993, p. 44 - 47.
  • Grant Mellor, "Quick as a Wink", Flying Tinsel, 1993, p. 56 - 59.
  • Rudolf F. Graf, "Charge a Balloon", Safe and Simple Electrical Experiments, p. 3.
  • Rudolf F. Graf, "Drawing Sparks From a Dry Newspaper", Safe and Simple Electrical Experiments, p. 6.
  • Rudolf F. Graf, "Building an Electrophorus", Safe and Simple Electrical Experiments, p. 16.
  • Rudolf F. Graf, "Using an Electrophorus", Safe and Simple Electrical Experiments, p. 17.
  • Joseph Frick, "# 269 - The Electrophorus", Physical Technics: Or Practical Instructions for Making Experiments in Physics and the Construction of Physical Apparatus with the Most Limmited Means, p. 303.
  • "The Electrophorus", Pike's Illustrated Catalogue of Scientific & Medical Instruments, 1984, p. 258.

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