Question

What is a Dielectric?

Answer 1

Dielectric

1. A dielectric is a type of insulator that becomes polarised when it comes in contact with an electrical field.
2. Electric charges do not flow naturally through dielectric materials when they come into contact with an electric field because they do not conduct electricity.
3. The charges do not flow, but they do migrate slightly away from their original place. A dielectric polarization is the result of this.
4. Because they lack free charge carriers, dielectrics are non-conducting materials.
5. Dielectric materials also have the advantage of not wasting energy in the form of heat while supporting an electrostatic field.

Dielectric Material

1. A dielectric material is a non-metallic material that has a high specific resistance, a negative temperature coefficient of resistance, and high insulating resistance.
2. When an electric field is applied to a dielectric, the electric charges do not flow through the material; instead, they move slightly from their usual equilibrium positions, resulting in dielectric polarisation.
3. Positive charges flow in the direction of the field, while negative charges shift in the opposite direction of the field due to dielectric polarisation. This event produces an internal electric field within the dielectric material, which lessens the total electric field.
4. These materials exist in solid, liquid, and gaseous forms. Some examples of dielectric materials are:
   • Solid Dielectrics – Ceramic, Plastic, and Glass
   • Dielectric Liquid – Distilled Water
   • Dielectric Gas – Dry Air, vacuum, and helium

Properties of Dielectric Material

1. The dielectric materials have a large energy gap.
2. The insulating resistance is high and the temperature coefficient of resistance is negative.
3. The resistivity of the dielectric materials is high.
4. The electrons' attraction to the parent nucleus is quite strong.
5. Because there are no free electrons to transport current, the electrical conductivity of these materials is extremely poor.

Application of Dielectric

1. Dielectrics are used to store energy like a capacitor.
2. A transformer's dielectric substance serves as both an insulator and a cooling agent.
3. High permittivity dielectric materials are utilized to improve the performance of semiconductor devices.
4. Electrets are a dielectric substance that has been treated to operate as an electrostatic substitute for magnets