Question

Plastic wire is a
(A) an insulator
(B) a conductor
(C) both of these
(D) none of these

Answer 1

Hint: Plastic cannot pass electric current. The electrical wires are covered with plastic coverings because the plastic is an insulator and thus it protects us from getting shocks.

Complete answer:
Conductor is an object or the type of material that allows the flow of charge in one or more directions. Materials current is generated by the flow of negatively charged electrons positively charged holes.
Insulator is a material in which the electron does not flow freely or the atoms of the insulator have tightly bound electrons whose internal electric charges do not flow freely. Insulators have very high resistivity. The most common example of an insulator is non metals. A much larger class of materials even though they may have lower bulk resistivity, are still good enough to prevent significant current from flowing at normally used voltages and thus are employed as insulation for electrical wiring and cables. Examples include rubber like polymers and most plastics which can be thermostat or thermoplastic in nature.

Thus option B is the correct answer.

Additional information:
All portable or handheld electrical devices are insulated to protect their use from harmful shock.
Class I insulation requires that the body and the others exposed metal parts of the devices be connected to earth via grounding wire. That is earthed at the main service pond but only needs basic insulation.
Class II insulation means that the device is double insulated. This is used on some appliances such as electric shavers, hair dryers and portable power tools. Double insulation requires that the devices have both basic and supplementary insulation, each of which is sufficient to prevent electric shock.

Note:
Insulators are non conducting materials with few mobile charges that support only insignificant electric current. A perfect insulator does not exist because even insulators contain small numbers of mobile charges which can charge current.