The circuit ofFigure P880emulates a typical 60-Hz residential power system. There are three wires entering the house, two are called hot and the remaining one is called the return or neutral. Each hot line is protected by a circuit breaker-but not the return. In the house, appliances such as lights, toasters, and electronics are connected between one of the hot wires and the neutral. Large appliances like ovens and dryers are connected between the two hot wires. Appliances are designed to operate with either 120 or 240 within a few volts either way.

(a)how that ifR₁andR₂are equal,I_N= 0 andV₁=V₂.

(b)Consider a typical power draw where aR₁is, for example, a 130- light bulb,R₂a 40- toaster, andR₃is a 10- clothes dryer. Find the phasorsV₁andV₂and findI_N.