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1. Electrical power is transmitted southwards from a hydroelectricplant over a distance of 1000 km via a DC (direct current)transmission line to a consumer. The output is 800 KV at the plant.The transmission line consists of one isolated aluminum strand with2.0 cm diameter; an identical cable returns back north to thegenerator. The resistivity of aluminum is 2.20 x 10-8 Ωm. The powerfed into the original transmission line at the plant is 1000MW.

   1. a) Draw a circuit diagram of the problem with power plant,transmission lines and a single resistor as consumer (load). Whatis the total current that flows out of the plant into thecable?

   2. b) How much power arrives at the consumer, i.e. is dissipated inthe load resistor, and what is the voltage one measures between theincoming and outgoing cable at the consumer?

   3. c) The utility company wants to decrease the power losses. Theyadd an identical cable in both directions in parallel to the firstone. If you assume the load resistor (consumer) and the outputvoltage of the power plant stay the same, what would be the newpower output of the plant and the fraction of power arriving at theconsumer?

   4. d) With now 2 strands in both directions, how would the loadresistor have to be set to get the original output power of 1000MWand what fraction of the power would arrive now at theconsumer?

   5. e) Briefly discuss if and how the power loss would change if thevoltage was increased or decreased, while the output power andresistances of load and transmission lines remain constant.