Which factor can affect the resistance of a wire?

• A. Length of the wire
• B. Temperature of the wire
• C. Material of the wire
• D. All of the above

Answer: (D)

All of the mentioned factors—length, temperature, and material—significantly influence the resistance of a wire, making the comprehensive choice the correct one.

The length of the wire is crucial because resistance increases with an increase in length; longer wires provide more material for the electric current to pass through, which impedes flow due to collisions with atoms within the wire.

Temperature also plays a vital role. As the temperature rises, the atoms within the conductor vibrate more vigorously, increasing collisions with the electrons flowing through, which in turn raises the resistance.

Lastly, the material composition directly affects resistance due to varying atomic structures and electron configurations. Different materials have different free electron densities, which determine how easily current can flow through them.

Understanding these three factors collectively provides a complete view of how wire resistance operates in electrical systems.