A capacitor or condenser is a device that stores electrical energy. It generally consists of two conductors carrying equal but opposite charges. Hence the total charge on any capacitor is always zero.
The ability of a capacitor to hold a charge is measured by a quantity called the capacitance.
The capacitance C, of a capacitor is defined as the ratio of the magnitude of the charge on either conductor to the magnitude of P.D. between them.
Expression for Capacitance of a Parallel Plate Capacitor
