Resistance is the tendency of a material to oppose the passage of electric current and convert electrical energy into heat, measured in ohms with the symbol R.
Resistance is the property of a material that opposes the flow of electric current through it, converting some electrical energy into heat in the process. Represented by the symbol R and measured in ohms, resistance is defined by the ratio of the applied voltage to the resulting current, a relationship expressed by Ohm's law. Every material has some resistance, from very low in good conductors to very high in insulators.
In conductors, low resistance is desirable so that current flows efficiently with minimal energy lost as heat. The resistance of a conductor depends on its material, length, and cross-sectional area, with longer and thinner conductors presenting more resistance. This relationship is central to sizing conductors for an application.
In commercial and industrial systems, conductor resistance affects voltage drop, signal loss, and heating over a cable run. Selecting conductors with appropriate resistance helps ensure that adequate voltage and signal reach equipment at the far end.
Because the resistance of a conductor depends on its material, length, and cross-sectional area, with longer and thinner conductors presenting more resistance, this relationship is central to sizing conductors so that adequate voltage and signal reach equipment at the far end of a run.
At Windy City Wire, the focus on quality conductors connects directly to resistance and how it affects performance. Supplying cable with conductors sized to keep resistance appropriate helps customers manage voltage drop and signal loss in their commercial and industrial systems.
Symbol R (resistance)