Today you can find the main formulas to calculate the electrical resistance of a cable. But first let’s look at some basics on resistance.
The electrical resistance is the opposition of electrons when moving through a conductor. Or in other words, the difficulty found by a current when traversing a closed electrical circuit, which allows slow or reduce the free flow of electrons.
According to the International System, the unit of resistance is the ohm, represented by the Greek letter omega (Ω), in honor of the German physicist Georg Ohm, who discovered that principle. Ohm is the resistance of a conductor when driving one ampere (current). Between its ends there is a potential difference (voltage) of a volt.