What is earthing and why is it essential?

• A. A protective coating for cables
• B. A low-resistance path to earth for fault currents, enabling protective devices to operate quickly and reducing shock risk.
• C. A method to insulate wires
• D. A technique to increase voltage drop

Answer: (B)

Earthing provides a low-resistance path to earth for fault currents, so protective devices can sense the fault and disconnect the circuit quickly. When a fault occurs, the current has a clear route to ground, which makes the overcurrent device (fuse or breaker) trip fast, reducing the risk of electric shock to anyone who touches exposed metal and minimizing damage to equipment. It also gives all metal parts a defined reference potential, helping keep voltages at safe levels even during faults.

The other options don’t fit because earthing isn’t a protective coating for cables, it isn’t a method to insulate wires, and it doesn’t purposefully increase voltage drop.