What is a Capacitor?
A capacitor consists of two conductors separated by a insulator. The insulator is often referred to as the dielectric. Examples of dielectric materials include glass, air, and paper. Capacitors each hold equal and opposite charges on the surfaces of the conductors. The dielectric develops an electric field. In SI units (International System of Units abbreviated SI from the French translation Système international d'unités), a capacitance of one farad means that one coulomb of charge on each conductor causes a voltage of one volt across the device.