in addition to current, voltage, and resistance, a fourth quantity is important in circuit analysis. This quantity is called Electrical power. Power is the rate at which work is done. Every time a circuit is energized, power is expended. Power is directly proportional to both current and voltage. This chapter looks at circuit applications involving
Resistive components in a circuit consume power. To determine the power dissipated by a component, multiply the voltage drop across the component by the current flowing through the component.
The total power dissipated in a series or parallel circuit is equal to the sum of the power dissipated by the individual components.