Question

Water has a large dielectric constant, but it is rarely used in capacitor. Explain why?

Answer 1

Explanation:

In an electric field the water molecules are polarized. But they are not at rest and can't induce charges to produce electric field like a solid dielectric. The motion of water molecules varies the capacity of a capacitance constantly. Therefore water can't be used as dielectric in a capacitor.

Answer 2

Due to polar properties will have a large value of conduction at certain voltage.

Explanation:

• Dielectric material is an insulator that can be polarized in the presence of an external electric field.
• The degree of polarization is measured by a constant called the dielectric constant or relative permittivity, which is equal to the polarization density/electric field.
• The dielectric constant of a metal/conductor is very complex (in some areas it is written that it is only determined for dielectric materials) and is frequency dependent.
• However, in terms of competition, we can take this infinity numerically. This is because the electric field inside the metal/conductor is zero and therefore infinite.