What are conductors and insulators and what do they do?

Part ofDesign and TechnologyElectronic control systems

Key points

  • Conductors allow electrical current to flow easily due to low resistance. Examples include copper, aluminium, and gold.
  • Semiconductors have electrical properties between conductors and insulators, used to control electrical current. Common materials are silicon, germanium, and gallium arsenide.
  • Insulators prevent electrical current flow due to high resistance. Examples include plastic, glass, and rubber.
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What are conductors?

White cable with 5 insulated copper twisted wires, red, brown, blue, black, and green and yellow copper wires against blurred background, closeup
Copper conductive wires in an electric cable
  • Most metals, like copper, aluminium, and gold, allow electrical current to flow through them easily due to their low electrical resistance.
  • The process of electrical current flowing through a wire is called conduction. Conductive materials are called conductors.
  • Examples of common conductors include copper wiring, circuit boards, electrical components, and the metal parts of electric plugs and sockets.
White cable with 5 insulated copper twisted wires, red, brown, blue, black, and green and yellow copper wires against blurred background, closeup
Copper conductive wires in an electric cable

What are semiconductors?

A close-up of a square microprocessor in place on a blue circuit board.
A computer chip contains semiconductor material
  • Semiconductors are materials that have electrical properties in between those of conductors and insulators.
  • They can be used to control the flow of electrical current, which is the basis for transistors and integrated circuits in electronic devices.
  • Common semiconductor materials include silicon, germanium, and gallium arsenide.
  • Examples of semiconductors include computer chips, diodes, and transistors.
A close-up of a square microprocessor in place on a blue circuit board.
A computer chip contains semiconductor material

What are insulators?

A plug made out of plastic
Plastic is a good insulator and is used to cover electrical components for safety
  • Non-metallic materials, such as plastic, glass, and rubber, do not allow electrical current to flow through them easily.
  • They have a high electrical resistance and are called insulators.
  • Insulators are used to prevent the flow of electricity, such as in the casing of electrical cables or the coating on wires.
  • Examples of insulators include plastic, rubber, glass, and ceramic.
A plug made out of plastic
Plastic is a good insulator and is used to cover electrical components for safety
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