Which of the following best describes real power?

Real power is defined as the actual power that performs work in an electrical circuit. It is measured in watts (W) and represents the energy consumed by electrical devices to produce useful work, such as turning a motor or lighting a bulb. This concept is crucial in understanding how efficiently electrical energy is converted to other forms of energy, such as mechanical or thermal energy.

The other choices describe different aspects of electrical power but do not adequately capture the essence of real power. Total power supplied to a circuit includes both real power and reactive power, which do not perform actual work. The statement regarding reactive and active power refers to components of a power system, where reactive power is needed for generating magnetic fields, and real power is the only component that brings about useful output. Lastly, kilovolt-amperes are a measure of apparent power, which includes both real and reactive power but does not represent the actual work done in the circuit. Therefore, the best choice for describing real power is the one that focuses on its ability to perform actual work.