130 kW (1.3 105 W) of power is delivered to the other side of a city by a pair of power lines between which the voltage is 12000 V.
(a) What current flows in the lines?
(b) Each of the two lines has a resistance of 5 ohms. What is the voltage change along each line? (Think carefully. This voltage change is along each line, not between the lines.)
(c) What power is expended as heat in both lines together (distinct from power delivered to customers)?
Do you see why it is so important to step voltages up with transformers for long-distance transmission?