What unit is used to measure resistance in an electrical circuit?

The unit used to measure resistance in an electrical circuit is the ohm. This unit is named after the German physicist Georg Simon Ohm, who formulated Ohm's Law that relates voltage, current, and resistance in an electrical circuit. Resistance quantifies how much a material opposes the flow of electric current, and it is represented by the symbol Ω.

Ohms play a critical role in circuit analysis and design, as understanding the resistance within a circuit helps in determining how much current will flow when a specific voltage is applied. This relationship is essential for ensuring that circuits operate correctly and safely.

The other units listed measure different electrical parameters: watts measure power, volts measure electrical potential difference, and farads measure capacitance. Therefore, none of these alternatives accurately represents the concept of resistance.