Which unit is used to measure electrical resistance?

Which unit is used to measure electrical resistance?

• A. Amperes (amps)
• B. Volts
• C. Ohms
• D. Watts

Answer: (C)

The concept here is how resistance is quantified. Resistance measures how much a component opposes current flow. The unit for that opposition is the ohm, symbolized by the Greek capital omega (Ω). One ohm is defined as the resistance between two points of a conductor when a constant potential difference of one volt, applied to those points, produces a current of one ampere, with no electromotive force in the conductor. In practical terms, Ohm’s law ties these ideas together: R = V / I. Since voltage is in volts and current in amperes, the result is in ohms. The other quantities—volts for voltage, amperes for current, and watts for power—are not units of resistance, which is why ohms is the correct choice.

The concept here is how resistance is quantified. Resistance measures how much a component opposes current flow. The unit for that opposition is the ohm, symbolized by the Greek capital omega (Ω). One ohm is defined as the resistance between two points of a conductor when a constant potential difference of one volt, applied to those points, produces a current of one ampere, with no electromotive force in the conductor. In practical terms, Ohm’s law ties these ideas together: R = V / I. Since voltage is in volts and current in amperes, the result is in ohms. The other quantities—volts for voltage, amperes for current, and watts for power—are not units of resistance, which is why ohms is the correct choice.