insulator

insulator

Substance that blocks or retards the flow of electric current or heat. An insulator is a poor conductor because it has a high resistance to such flow. Electrical insulators are commonly used to hold conductors in place, separating them from one another and from surrounding structures to form a barrier between energized parts of an electric circuit and confine the flow of current to wires or other conducting paths. Electrical insulators include rubber, plastic, porcelain, and mica. Thermal insulators. which break up the heat-flow path by absorbing radiant heat, include fiberglass, cork, and rock wool.

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insulator

A material that does not conduct electricity. Contrast with conductor.

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insulator [′in·sə‚lād·ər]

(electricity)

A device having high electrical resistance and used for supporting or separating conductors to prevent undesired flow of current from them to other objects. Also known as electrical insulator.

(materials)

A material that is a poor conductor of heat, sound, or electricity.

(solid-state physics)

A substance in which the normal energy band is full and is separated from the first excitation band by a forbidden band that can be penetrated only by an electron having an energy of several electronvolts, sufficient to disrupt the substance.