Which unit would be used to express power?

Power is expressed in watts, which is the standard unit for measuring electrical power in an electrical circuit. The watt quantifies the rate at which energy is used or generated. Specifically, one watt is defined as one joule per second, reflecting the energy transfer over time.

In electrical terms, power is calculated using the formula ( P = V \times I ), where ( P ) is the power in watts, ( V ) is the voltage in volts, and ( I ) is the current in amperes. This relationship highlights how power is directly tied to both voltage and current, solidifying watts as the correct unit for expressing power.

Other units mentioned in the options serve different functions: volts measure electric potential, amperes measure electric current, and ohms measure resistance. Each of these units is essential in understanding electrical systems but none is used to express power itself. Thus, watts stand out as the only unit dedicated to quantifying power.