Why copper and aluminium wires are usually employed for electricity transmission?

Copper and aluminium wires are commonly used for electricity transmission for several reasons:

1. High Electrical Conductivity: Both copper and aluminium have high electrical conductivity. This means they can easily carry electrical current. Copper, in particular, has the highest conductivity of any non-precious metal.

2. Ductility: Both metals are ductile. This means they can be drawn into thin wires without breaking. This property is crucial for the manufacturing of electrical wires.

3. Tensile Strength: They have sufficient tensile strength. This means they can withstand the tension of being strung between transmission towers.

4. Cost-Effectiveness: While copper is more conductive, aluminium is more cost-effective. Aluminium has only 61% of the conductivity of copper, but it only has about 30% of the weight. This makes aluminium a more economical choice for long-distance power transmission.

5. Corrosion Resistance: Both metals are resistant to corrosion, which is important for outdoor installations where the wires are exposed to the elements.

6. Availability: Both copper and aluminium are widely available, making them a practical choice for widespread use in electrical transmission.