Question 1: Define the function of the Live wire in an electrical circuit.

Answer: The Live wire carries current from the power source to the appliance, providing the voltage needed for operation.

Question 2: Explain why the Neutral wire is considered at or near zero voltage relative to the ground.

Answer: Because it is connected to the earth at the transformer substation, maintaining a voltage close to zero for safety and circuit completion.

Question 3: Describe the primary safety function of the Earth wire in household wiring.

Answer: The Earth wire provides a safe path for electrical current to flow into the ground if a fault occurs, preventing electric shock.

Question 1: A household appliance operates at a voltage of 230 V and has a current of 5 A. Calculate the power consumed by the appliance in watts.

Answer: Power (W) = Voltage (V) × Current (A) = 230 V × 5 A = 1150 W

Question 2: If a fuse rated at 13 A is used in a circuit with a voltage of 230 V, what is the maximum power (in watts) that the fuse can safely carry?

Answer: Maximum Power = Voltage × Fuse Rating = 230 V × 13 A = 2990 W

Question 1: List three safety precautions to observe when working with mains electrical wiring at home.

Answer: Turn off the power supply before working on wiring, use insulated tools, and ensure proper grounding of the Earth wire.

Question 2: Explain why it is dangerous to touch the Live wire while holding the Neutral wire.

Answer: Because the Live wire has a high voltage relative to ground, touching it can cause an electric shock, especially if the Neutral is also connected to ground, completing the circuit.

Question 1: A single-family house has a main supply voltage of 240 V. The Earth wire is connected properly, but during testing, a short circuit occurs between the Live and Earth wires. Describe what safety feature in the system helps prevent electrical shock or fire in this situation.

Answer: The circuit breaker or fuse detects the excess current caused by the short circuit and disconnects the supply, preventing electric shock, overheating, or fire.

Question 1: In modern electrical appliances, why is the Earth wire often connected to the metal casing, and how does this improve safety?

Answer: Connecting the Earth wire to the metal casing ensures that if a live wire touches the casing, the current is safely directed into the ground, triggering safety devices and preventing electric shocks.