Lineman Practice Test 2025 – All-in-One Resource to Master Your Certification!

Resistance in electrical circuits is measured in ohms. The ohm is the derived unit of electrical resistance in the International System of Units (SI). It is defined as the amount of resistance that allows one ampere of current to flow when one volt of electrical potential is applied across it. This relationship is expressed in Ohm's Law, which states that voltage (in volts) equals current (in amperes) multiplied by resistance (in ohms).

Understanding this measurement is crucial for linemen and others working in electrical fields, as it impacts everything from circuit design to troubleshooting. Resistance affects how much current can flow through a conductor for a given voltage, which is fundamental in ensuring electrical systems operate safely and efficiently. The other units listed are associated with different electrical quantities: volts measure electric potential, watts measure power, and amperes measure current, but they do not represent resistance.