ABSTRACT
Resistance is the property of a conductor, which determines the flow of electrical current. We calculate the resistance of a conductor by applying a potential difference between two points on the conductor, measuring the current, and dividing:
R ¼ V I
ð1Þ
where R is resistance, V is the potential difference, and I is current. This expression is known as Ohm’s law. The SI unit for resistance is ohms, abbreviated as O.