Question

‘X’ is a type of commercial resistor made from a mixture of clay, carbon black, and resin binder which are pressed and then molded into cylindrical rods by heating. Identify X.

(a) Wire-bound resistors

(b) Carbon resistors

(c) Metal film resistors

(d) Surface-mount resistors

This question was posed to me in a national level competition.

The doubt is from Current Electricity topic in section Current Electricity of Physics – Class 12

Answer 1

Right answer is (b) Carbon resistors

Easiest explanation: Carbon resistors are made from a mixture of carbon black, clay and resin binder which are pressed and then molded into cylindrical rods by heating. The rods are enclosed in a ceramic or plastic jacket. They are used in circuits of radio receivers, amplifiers, etc.