What is the unit of resistance in an electrical circuit?

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

Answer: (D)

The unit of resistance in an electrical circuit is the Ohm. This unit is named after Georg Simon Ohm, a German physicist who formulated Ohm's Law, which defines the relationship between voltage, current, and resistance in an electrical circuit. According to Ohm's Law, the resistance (measured in Ohms) is defined as the ratio of voltage (measured in Volts) across an element to the current (measured in Amperes) flowing through that element. Therefore, the Ohm effectively quantifies how much a material opposes the flow of electric current.

Understanding this concept is essential for anyone studying basic electricity, as it lays the groundwork for analyzing and designing electrical circuits.