Typically, a Leyden jar comprises a glass jar coated inside and outside with unconnected metal foils, and a conducting rod which passes through the jar's insulated stopper to connect with the inner foil. Effectively, then, there are two conductors, the one almost completely enclosed by the other, and separated from it by the thickness of the dielectric (the glass). If either conductor is connected to earth, and the other insulated and charged (usually from an electrostatic generator), an opposite and nearly equal charge is induced in the former.
Leyden jars were used to carry out many early experiments in electricity but are now little used outside the classroom.
Related category• ELECTRICITY AND MAGNETISM
Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact