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Maxwell's Laws Tour

Electric Law by Experiment

Gauss's electric law states that the total flux passing thru a closed surface is always equal to the total charge enclosed by that surface. If we charge a metallic sphere and place a surface around it the total flux passing through the surface is equal to the charge on the surface of the sphere. What if we try to "shield" the sphere with a larger, hollow conducting sphere? When the larger sphere is brought close to the smaller sphere the negative charges on the large sphere are attracted to the positive ones on the small sphere and essentially cancel out. This then leaves a net positive charge on the outside sphere equal to the original charge on the small sphere. This was an experiment used often to show the validity of Gauss's electric law. It was called the Ice Pail Experiment because ice buckets where often used in place of the conducting spheres.