5B20.20 - Butterfly Net

Charge the butterfly net with one of the charging rods.  With the small paddles show that the charge is on the outside of the butterfly net and not on the inside.  Using one of the strings connected to the inside of the net, turn the net inside out and show once again the charge is still on the outside.
Code Number:
5B20.20
Demo Title:
Butterfly Net
Condition:
Excellent
Principle:
Corona Discharge, Surface Charge Density
Area of Study:
Electricity and Magnetism
Equipment:
Electrometer and sensing cage, two small paddles, butterfly net, charging rods, and clothes.
Procedure:

Charge the butterfly net with one of the charging rods.  With the small paddles show that the charge is on the outside of the butterfly net and not on the inside.  Using one of the strings connected to the inside of the net, turn the net inside out and show once again the charge is still on the outside.

References:
  • Thomas B. Greenslade, Jr., "Faraday's Bag (Photo)", AJP, Vol. 70, # 12, Dec. 2002, p. 1215. (Reprinted AJP, Vol. 72, # 1, Jan. 2004, p. 75.)
  • Ea-18, 19, 21:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • John Henry Pepper, "Faraday's Experiment with the Conical Muslin Bag", Cyclopadic Science Simplified, 1901, p. 232.

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