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Question
Give a scientific reason:
For electric power transmission, copper or aluminium wire is used.
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Solution
- Copper and aluminium have very low resistivity, hence less resistance for long wires.
- Low resistance causes less I2R heat loss, so energy loss is reduced.
- Both are good conductors that allow large currents to pass safely.
- Aluminium is lighter and cheaper, copper has higher conductivity; both are ductile and can be drawn into long wires.
Therefore, copper or aluminium wires are used to transmit electricity.
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