Standard Science Primary 5 Systems

Why is the wire inside an electrical cord made of copper, while the outside covering is made of plastic?

A Copper is an insulator, and plastic is a conductor.
B Copper is flexible, and plastic prevents it from melting.
C Copper is cheap, and plastic looks nice.
D Copper is a conductor to carry current, and plastic is an insulator to protect from shocks.
Show Worked Solution

Worked Solution

Step 1: A circuit needs a conductor to allow electricity to flow. Copper is an excellent metal conductor. Step 2: To prevent electric shocks when handling the wire, it must be covered by a material that stops current flow. Step 3: Plastic is a non-metal insulator.

Correct answer: Copper is a conductor to carry current, and plastic is an insulator to protect from shocks.

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