5A40.30 - Electrostatic 2x4

Code Number:
Demo Title:
Electrostatic 2x4
Electrostatic Repulsion and Attraction, Induction
Area of Study:
Electricity & Magnetism
2 X 4 Board, Watch Glass Pivot on Stand, Electrostatic Rods, Cat's Fur and Silk, Meter Sticks, and Aluminum Meter Stick.

Hold a charged rod near the end of the 2 X 4 and observe the board move slowly toward the rod. Both the plus charged and minus charged rods will show this behavior. The Fun Fly Stick may be substituted for the charged rod when working in a humid environment.

The wooden and aluminum meter sticks work exactly as the 2 X 4 described above even though one is an insulator and one is a conductor.

  • Cristos Deligkaris, "A Classroom Activity for Teaching Electric Polarization of Insulators and Conductors", TPT, Vol. 56, #4, Apr. 2018, p. 236.
  • Sheldon Wortzman, "A Large-Scale Electroscope", TPT, Vol. 19, #7, Oct. 1991, p. 481.
  • R. A. Egler, "Simple Conservation of Energy Experiment for Introductory Labs", Department of Physics, North Carolina State University, page 8.
  • Borislaw Bilash II, David Maiullo, "Moving Mountains", A Demo a Day, p. 245.
  • The Science House, "An Electrostatic Compass", Physics From the Junk Drawer, p. 31.
  • Stangl, "34 Electrostatic Action", Science Toolbox, p. 84.
  • Tik L. Liem, "The Electric Meter Stick", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 85.
  • Rudolf F. Graf, "The Magic Finger", Safe and Simple Electrical Experiments, p. 29.
  • Borislaw Bilash II, “The Magic Wand“, A Demo A Day – A Year of Physical Science Demonstrations, p. 275.

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