Question

How does the resistance of a conductor vary with temperature?

Answer 1

A conductor is an object or type of material that allows the flow of charge in one or more directions. Resistance is a measure of the opposition to current flow in a conductor or an electrical circuit. When a potential difference is placed across a conductor, it helps electron flow, whereas resistance opposes electron flow.

Complete answer:
The movement or flow of electrically charged particles in a conductor is known as electric current. When an electric current flows through a conductor, it moves through the metal as a drift of free electrons. Because the electrons in a conductor are free to roam around, electricity flows readily through it. A current of electricity is formed whenever electrons travel across a conductor. The ions in the conductor can clash with the moving electrons. This produces resistance and makes it more difficult for the electricity to flow.

When the atoms in a metallic conductor are heated, they vibrate with greater amplitude and frequency. The thermal velocity of free electrons increases as the temperature rises. This raises the resistance of the conductor and thus the opposition to electron mobility.With increasing temperature, the resistance of the conductor increases as the number of collisions within the conductor increases, decreasing the flow of current.

Hence, with increasing temperature, the resistance of the wire increases and vice versa.

Note: Resistance also varies with the length and thickness of the conductor.Resistance increases with an increase in the length of the conducting wire. Resistance decreases with an increase in the thickness of the wire.