Definition - What does Insulator mean?
Insulator is a substance with internal electric charges which do not flow freely and hence make it impossible for conducting an electric current. Insulators are different from other materials, conductors and semiconductors that easily conduct electric current. Insulators' resistivity property distinguishes them from conductors and semiconductors. Conductors and semiconductors have a lower resistivity than Insulators. They are used in electrical equipment to separate and support electrical conductors without allowing electric current to pass through them.
Petropedia explains Insulator
Insulators block a free flow of electrons from one atom to other and one molecule to another molecule. They sometimes suffer from electrical breakdown when they are subjected to high voltage. They play a vital role in the electrostatic demonstrations and experiments. They are applied in a very thin coating to cable and electric wires which are known as insulated wires. When they are used for high-voltage power transmissions, they are made from glass, composite polymer materials or porcelain. They are also used to support the wires without letting the current flow to the ground through a tower.
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