IBEW Electrical Practice Test 2025 – Complete Exam Preparation

Electrical resistance is measured in Ohms, which is the correct answer. The Ohm is the standard unit in the International System of Units (SI) for quantifying resistance in an electrical circuit. It is defined as the resistance between two points in a conductor when a constant potential difference of one volt applied across those points produces a current of one ampere.

Understanding resistance is crucial in electrical engineering and circuit design, as it affects how much current will flow in response to a given voltage. The relationship between voltage, current, and resistance is described by Ohm's Law, which states that the current (I) through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R). Thus, Ohm's Law is often expressed as: V = I × R.

Knowing the units of measurement in electrical contexts, such as Ohms for resistance, allows for better comprehension of how circuits function, ensuring accuracy in calculations and applications related to electrical systems. The other units—Volts measure voltage, Amperes measure current, and Watts measure power—serve different purposes in the study of electricity but do not represent resistance.