What affects the resistance of a conductor?

Resistance in a conductor is influenced by several key factors, and all of these factors play a significant role in determining the overall resistance.

The length of the conductor is crucial because, generally, the longer the conductor, the higher the resistance. This is due to the increased likelihood of collisions between charge carriers (electrons) and the lattice structure of the material, which impedes the flow of electric current.

The thickness of the material also impacts resistance. A thicker conductor has a larger cross-sectional area, allowing more paths for the charge carriers to move through. This results in lower resistance compared to a thinner conductor of the same material and length.

Additionally, the temperature of the material affects its resistance. As temperature increases, the atoms in the conductor vibrate more, leading to more collisions between the charge carriers and the atomic lattice. This typically results in increased resistance, especially in metals, which exhibit a positive temperature coefficient of resistance.

Therefore, all these factors—length, thickness, and temperature—are integral to understanding how resistance in a conductor works, making "All of the above" the correct choice.