How does temperature generally affect the resistance of conductors?

• A. Resistance increases with temperature
• B. Resistance decreases with temperature
• C. Resistance remains constant with temperature
• D. Resistance is unaffected by temperature

Answer: (A)

Resistance in conductors is influenced by temperature due to the motion of atoms within the material. As temperature increases, the atoms in a conductor vibrate more intensely. This increased atomic activity can impede the flow of electrons, leading to a higher resistance. This phenomenon is commonly observed in metallic conductors, where the temperature coefficient of resistance (a measure of how much the resistance changes with temperature) is typically positive. Therefore, when the temperature rises, it results in more collisions between the free electrons (which carry the electric current) and the vibrating atoms, causing the resistance to increase. This understanding is fundamental in electrical systems, particularly for applications where temperature variations can significantly impact performance.