Why is the earth pin thicker and longer than the live and the neutral pins? What is the advantage of earth wire connection in domestic appliances? [3 MARKS]
Each point: 1 Mark
1. It is thicker beacuse a large cross sectional area as compared to other pins makes its resistance lower than other pins so that in case of any short circuit, the excess current flows through the earth pin.
2. It is made longer so that it gets connected to the earth terminal earlier than the live and neutral pins. This ensures the safety of the user.
3. Earth wire is connected to the metallic case of an electrical appliance to protect from electric shock by transferring excess amount of current to the earth.