Question

The self-inductance of a straight conductor is.
(A) Zero
(B) Infinity
(C) Very large
(D) Very small

Answer 1

Hint: We will first understand the term inductance and its types. Inductance can be defined as the tendency of an electrical conductor that opposes any change in the electric current that is flowing through that conductor. The flow of electric current is responsible for the creation of a magnetic field around the conductor.

Complete step by step solution:
Inductance can be categorized into two types. Self-inductance and another type is mutual inductance. Self-inductance can be defined as the property of the coil which opposes the change of current flowing through the coil. Inductance in the coil is occurring by the means of the self-induced emf produced in the coil itself due to a change in the electric current flowing through the coil.
Hence if the current in the coil tends to increase, the self-induced emf which is produced in the coil will try to oppose the rise that occurs in the current and that means the direction of the emf induced can be given to the opposite direction of the voltage applied.
Similarly, if the current in the coil tends to decrease, the self-induced emf in the coil produced is in such a direction that will oppose the fall of current, which means that the direction of the self-induced emf can be considered as same as that of the applied voltage.
As discussed self-inductance is observed in the case of coil and coil consists of some numbers of turns. But in the case of straight conducting wire, the number of turns is zero. As the self-inductance is given as proportional to the number of turns of the coils. Therefore in the case of a straight conductor, the self-inductance is always zero.

Hence option (A) is the correct answer.

Note: Another type of inductance is mutual inductance which can be defined as the property of the given coil due to which it opposes the change of current in the other coil or neighboring coil that is associated with it. Mutual inductance always occurs associated with the two coils.