Which of the following statements about electric wires is NOT true?

The correct answer is Option (3) → The third is the earth wire that has pink insulation and this is connected to a metallic body deep inside earth. It is used as a safety measure to ensure that any leakage of current to a metallic body does not give any severe shock to a user.

The question asks for the statement that is NOT true. In Indian house wiring, the supply comes on a live wire (red insulation) and a neutral wire (black insulation), and a third, earth wire (green insulation), is added for safety.

Option (1) The wire of black insulation, is a neutral wire. — True (Incorrect). The neutral wire, kept at zero potential, has black insulation.

Option (2) In our houses we receive AC electric power of 220 V with a frequency of 50 Hz. One of the wires in this supply is with red insulation, called live wire. — True (Incorrect). India’s mains supply is 220 V AC at 50 Hz, and the live (positive) wire carries red insulation.

Option (3) The third is the earth wire that has pink insulation … — Not true (Correct). Everything else in the statement is right: the earth wire is joined to a metal plate buried deep in the earth, and a current leaking to the metal body of an appliance flows to the earth instead of through the user. But the earth wire has green insulation, not pink.

Option (4) The electric wires used in houses are generally made of copper. — True (Incorrect). Copper is used because it has very low resistance and bends without breaking.