Two simple ways of verification of the 1/r2 dependence in Coulomb's law atboth high school and university level
2014
Abstract
This article describes two simple and inexpensive ways how to demonstrate and to verify the Coulomb"s law. The first part presents the classical way of Coulomb"s law demonstration (using two charged balls).
But the most precise experiments performed in the 20th century utilize the equivalence of 1/r2 dependence and the fact that the electric field inside a charged conductive sphere is zero. In the second part we present low-cost variant of such experiment using simple home-made detector of electric field with FET transistor.