Electroscopes, Plexiglas or PVC Rods, Cats Fur, and Silk

 

Code Number: 5A40.16

Demo Title: Induction - Charging Electroscope by Induction

Condition: Good

Principle: Electrostatics

Area of Study: Electricity & Magnetism

Equipment: 

Electroscopes, Plexiglas or PVC Rods, Cats Fur, and Silk.

Procedure:

Rub the PVC rod with the cats fur.  Bring the cats fur near the ball of the electroscope.  Touch the ball of the electroscope with your finger.  As you move the cats fur away the electroscope should remain charged.  This charge should be opposite of the charge held by the PVC rod (negative).  

Repeat the steps with the Plexiglas rod and silk.

References:

  • Richard S. Halada, "Electrons and Post-itTMtrons", TPT, Vol. 29, # 8, Nov. 1991, p. 543.
  • Nobuo Naba, Oleg Jefimenko, "How Can an Electroscope be Charged This Way?", TPT, Vol. 17, # 1, Jan. 1979, p. 56.
  • Zenon Gubanski, "Conversation of Charge", TPT, Vol. 8, # 5, May 1970, p. 269.
  • Mario Iona, "Electroscopes Do Not Measure Charge", TPT, Vol. 8, # 8, Nov. 1970, p. 466.
  • "Charging of an Electroscope", TPT, Vol. 3, # 4, April 1965, p. 185.
  • "Charging an Electroscope by Induction",  TPT, Vol. 3, # 1, Jan. 1965, p. 29.
  • E-135:  "Electroscope - Leaf & Electronic", DICK and RAE Physics Demo Notebook.
  • Tik Liem, "The Induced Charge", Investigation to Science Inquiry, p. 245.
  • Robert A. Morse, "Laboratory Activity 7: Two Plate Induction", Teaching about Electrostatics, p. 3 - 20.
  • Janice VanCleave, "66, Fluttering Butterfly", Teaching the Fun of Physics, p. 102.
  • "180, Inductive Charges?",  Christopher P. Jargodzki and Franklin Potter,  Mad About Physics, p. 69, 211.
  • W. Bolton, "Induction of Charge", Book 4 - Electricity, Physics Experiments and Projects, 1968, p. 22-23.
University of Maryland Physics Department QOTW Question #129
University of Maryland Physics Department QOTW Answer #129
 
5A40.60 Induction - Electroscope
5A40.16 - University of Maryland QOTW Question #129
5A40.16 - University of Maryland QOTW Answer #129