Capacitors (C) is an electrical component used for storing
electric charge temporarily (like small batteries). In
general, a capacitor consists of two metallic plates
separated by a thin layer of insulator (called a dielectric),
that can be represented by a parallel plates model, as
shown in Fig.1(a).
Figure 1(a) Parallel plates model (b) cutaway drawing of a
typical capacitor.
The capacitance (C) of a capacitor is the amount of
electric charge it can store for every volt applied to it.
From the relation, C = Q/V, the capacitance is therefore
measured in Coulomb per volt or Farad.
From the above equation, a capacitor should store more
charge when the external applied voltage is increased.
However, we cannot increase the capacitance of a
capacity just by increasing the applied voltage. In order to
make a better (higher C) capacitor, it must be made in a
different way, based on the following equation.