Question

Electrical wires have a coating of an insulated material. The material generally use is:
A. Sulphur
B. graphite
C. PVC
D. None of these

Answer 1

Hint:It is a synthetic plastic polymer formed from the polymerization reaction of its monomer. Due to its characteristics it has wide application in making pipes, windows, and in making bottles. Due to its low conduction of electricity, it is used in electronics equipment.

Complete answer:
Electricity is produced when flow of charge within the system takes place by applying external current.
Electrical wires are generally made up of copper for conduction of electricity. If the wires are kept naked, there are high chances of getting shock from electricity due to high flow of charge and causing short circuits and fires. To avoid these severe accidents, the electrical wires are coated with an insulated material.
The insulators are generally the material where the atoms are bonded so tightly that the flow of charge is very low. Therefore, they cannot conduct electricity.
Graphite is a good conductor of electricity, therefore it cannot be used for coating electrical wires.
Poly vinyl chloride is a polymer with good insulating properties. It is formed from polymerization of its monomer vinyl chloride. It has high dielectric constant and volume resistivity which make it suitable for low voltage insulating material. Thus, it is used in coating the electrical wires to protect from severe shock and short circuit.
Therefore, the correct option is C.

Note: Sulphur is also an insulator but it is brittle in nature, therefore it cannot be used for coating of electrical wires.Sulphur is a multivalent non-metal, abundant, tasteless and odorless. In its native form sulphur is a yellow crystalline solid. In nature it occurs as the pure element or as sulfide and sulfate minerals.