A material that responds with very high resistance to the flow of electrical current or totally resists electric current is called an insulating material. In insulating materials, the valence electrons are tightly bonded to their atoms.
In the electrical field, the purpose of any insulating material is to separate electrical conductors without passing current through it. Material like PVC, glass, asbestos, rigid laminate, varnish, resin, paper, Teflon, and rubber are very good electrical insulators. The insulating material is used as a protective coating on electrical wire and cables.
The most significant insulating material is air. Besides that solid, liquid, and gaseous types of insulators are also used in electrical systems.
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