What unit of power is used in direct current electrical circuits?

In direct current (DC) electrical circuits, the unit of power is measured in watts. Power represents the rate at which electrical energy is transferred or converted and is calculated using the formula: Power (P) = Voltage (V) × Current (I).

In this context, voltage is measured in volts, and current is measured in amperes. When these two quantities are multiplied, the resulting unit of measurement becomes watts. This relationship illustrates how power is dependent on both the voltage supplying the circuit and the current flowing through it.

The other units listed—amperes, volts, and ohms—serve different functions in electrical systems. Amperes measure the flow of electric current, volts measure the electrical potential difference, and ohms measure electrical resistance. While these are all crucial components in understanding electrical circuits, they do not denote power directly like watts do. Thus, watts is the appropriate choice when discussing power in the context of direct current electrical circuits.