Question

When current flows through a conductor, its temperature
A. increases
B. decreases
C. remains same
D. may increase or decrease

Answer 1

When electrons flow through a conductor, current flows through the conductor. When the electrons collide with the atoms of the conductor, they transfer heat to the conductor atoms. Using this concept with the help of joule heating effect, give the answer to the question.

Complete step by step answer:
The answer to this question can be given with the help of the Joule heating effect. The joule heating effect is also called the resistive heating or the ohmic heating. According to the joule heating effect, the energy of the electric current is converted into heat energy when it flows through a resistance.

If we consider any conductor or solid or liquid, the conductivity of the materials will be always finite. So, resistance will be present in every material. When electric current flows through any material with finite conductivity, electric energy is converted into heat energy due to the resistive loss in the material.

When the conduction electrons flow through the material, the electrons transfer their energy to the conductor’s atoms through collision. Due to this transfer of energy through collision, the heat is generated in the conductor. So, the temperature of the conductor increases because of the current flow through it.
So, we can say that when electric current flows through a conductor, the temperature of the conductor rises.
Hence, the correct answer is option A.

Note:
The heating effect of a conductor depends on 3 factors. The higher the resistance of the conductor, the higher will be the heat produced. The heat produced is proportional to the time for which the current is flowing through the conductor. The amount of heat generated also depends on the amount of current flowing through the conductor.