ANSWERS: 2

Resistance is directly related to power loss. Basically it means that the longer the conductor, the larger it needs to be. A personal experience: an extension cord made of 14 gauge wire at 200 feet of length will only deliver about 90 of the 115 volts it is plugged into. A cord the same length of 10 gauge wire, will deliver all of the 115 volts. This was discovered on a construction site when one of the guys couldn't get his air compressor to run right. The electrician tested the voltage on the cord with a digital meter to show us the problem.

252017 Imagine two atoms and an electron moves from one to the other. It takes voltage to move that electron, and when it moves, that is a current. So that ExI is the minimum power loss associated with that material, and E/I is the resistance. If the path is longer then the voltages add up but the current is still the same. If you have two pairs side by side then the voltage is the same but there is twice the current. So the resistance is proportional to the length of the path, and inversely proportional to the area.
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