The ohm is the unit of electrical resistance, reactance, and impedance, symbolized by the Greek letter omega, defined so that one volt drives one ampere through one ohm.
The ohm is the standard unit for electrical resistance, reactance, and impedance, represented by the Greek letter omega. It is defined by the relationship among voltage, current, and resistance: one ohm is the resistance through which a constant potential difference of one volt drives a current of one ampere. The ohm quantifies how strongly a circuit or component opposes the flow of electricity.
Resistance, reactance, and impedance all describe opposition to current under different conditions, and all are measured in ohms. In cable, the impedance expressed in ohms is a defining characteristic, particularly for coaxial and data cable, where a consistent impedance such as a common value in ohms is essential to preserving signal quality.
In commercial and industrial systems, values in ohms appear throughout specifications, from the resistance of conductors to the characteristic impedance of signal cable. Understanding the ohm is fundamental to interpreting these specifications and matching cable and components correctly.
Because impedance expressed in ohms is a defining characteristic of signal cable, the unit appears constantly in coaxial and data specifications, where a consistent value is essential to preserving signal quality across a run from source to destination.
At Windy City Wire, the focus on quality low-voltage cable connects directly to characteristics expressed in ohms, including conductor resistance and cable impedance. Understanding the unit helps customers interpret specifications and match cable to the electrical requirements of their applications.
Symbol: omega (the ohm)