Q = C V

Example

The relationship between the voltage, charge and capacitance of a capacitor is:

Q = C V

where:

V = voltage across the capacitor (in volts or V)
Q = the charge on the plates of the capacitor (in coulombs or C)
C = the capacitance of the capacitor (in farad or F).

The charge on the plates of a capacitor in the diagram at right is 6C. The capacitance of the capacitor is 3F. Hence the voltage is:

V = Q/C = (6C)/(3F) = 2V.