5A40.10 - Electrostatic Spheres

Code Number:
Demo Title:
Electrostatic Spheres
Area of Study:
Electricity & Magnetism
Electrophorus, Charging Rods and Silk or Cat's Fur, electrostatic Spheres.

Charge one of the electrostatic spheres with the desired Rod or the Electrophorus.  The uncharged sphere can be touched to the charged sphere if you wish to have both spheres with the same charge.  

If you wish to show induction, bring the uncharged sphere near the charged sphere and then touch the back side of the uncharged sphere with your finger.  Now the two spheres should have opposite charges which can be shown with the Pasco Electrometer or a set of pith balls.

  • Josip Slisko and Raul A. Brito-Orta, "On Approximate Formulas for the Electrostatic Force Between Two Conducting Spheres", AJP, Vol. 66, #4, Apr. 1998, p. 352.
  • W. L. Schaich and S. Mahmud, "On the Distribution of Charge Over the Surface of a Conductor", AJP, Vol. 59, #7, July 1991, p. 656.

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