Two wires, one of copper and other of iron, are of the same length and same radius. Which will have more resistance? Give reason.
Two wires, one of copper and other of iron, are of the same length and same radius. Which will have more resistance? Give reason.

Iron has a higher resistivity than copper, which has a lower resistance. As a result, the higher the resistivity, the larger the resistance; conversely, the lower the resistivity, the lower the resistance. As a result, iron wire of the same length and radius has higher resistance than copper wire of the same length and radius.