What is the unit of electrical resistance?

• A. Volt
• B. Watt
• C. Ohm
• D. Ampere

Answer: (C)

The unit of electrical resistance is the Ohm. This unit quantifies how much a material opposes the flow of electric current. According to Ohm's Law, resistance (R) can be understood in the context of voltage (V) and current (I) with the formula R = V/I. In this relationship, Ohm serves as the measurement that reflects how much voltage is required to push a certain amount of current through a resistance.

Understanding resistance is crucial in electrical applications as it determines how circuits operate. The lower the resistance, the easier it is for current to flow; conversely, higher resistance can impede current, affecting overall performance.

The other units listed have distinct roles in electrical theory but do not measure resistance. Voltage is measured in volts, power in watts, and current in amperes. Each of these units has specific applications and contexts in electrical work, but when it comes to resistance specifically, the Ohm is the definitive unit.