Resistance

Resistance is the opposition to current flow. The resistance of an object depends on the width, length and the material of which the object is made. It is represented by R and is calculated as:

where:

ρ is the resistivity of the material (in Ω)

L is the length

A is the cross-sectional area

The unit of resistance is ohms (Ω). One ohm is equal to one volt per ampere.