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What Does Dielectric Mean?

A dielectric material is a
type of insulator which becomes polarized when it comes in contact with an
electrical field. It can easily support an electrostatic field even though it is
not a conductor of electricity. Such materials are used in many places such as
in capacitors and radios, as well as transmission lines for radio frequency. It can be used to store energy too, if it is configured properly.
Most of these materials are solid in nature, but some fluids and gasses also exhibit
dielectric properties. An example of such a gas is dry air, while examples of
solid dielectrics include mica, ceramic, plastics and glass. Distilled water is a dielectric liquid.


Techopedia Explains Dielectric

As dielectric materials are
not conductors, electric charges do not flow normally through them when they
come in contact with an electric field. The charges do not actually flow, but move
slightly from their original position. This results in a dielectric polarization. It causes the positive charge in the material to go toward the
electrical field and the negative charges to do the opposite. Thus, an
electrical field is created in the material itself and it reduces the overall
field of the material. If the molecules of the material are bonded weakly, then
they even realign themselves based on their symmetry axes. Another major
property of dielectric materials is that they do not waste energy in the form of
heat while supporting an electrostatic field. This property exhibited by
certain materials, allowing the creation of high-grade capacitors.


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Margaret Rouse
Technology Expert
Margaret Rouse
Technology Expert

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.