Which of the following factors does not affect the electric resistance of wire?
Answer Details
The factor that does not affect the electric resistance of a wire is mass. Electric resistance is the opposition to the flow of electric current through a conductor. The four factors that affect the resistance of a wire are length, temperature, cross-sectional area, and the type of material used to make the wire.
Length: the longer the wire, the higher the resistance as the electric current has to travel further, experiencing more collisions with the wire's atoms and electrons, which leads to a higher resistance.
Temperature: an increase in temperature leads to an increase in the wire's resistance. This is because as the temperature increases, the wire's atoms and electrons vibrate more, impeding the flow of current, thus increasing the resistance.
Cross-sectional area: the larger the wire's cross-sectional area, the lower its resistance because there are more paths for the electric current to flow through, reducing the chances of collisions with atoms and electrons, thus reducing resistance.
Type of material used: different materials have different numbers of free electrons, which affects their resistance. For example, copper has more free electrons than iron, and therefore has a lower resistance.
Mass, on the other hand, does not affect the resistance of a wire. The mass of a wire is not related to the number of free electrons or the wire's ability to impede the flow of current.