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P. 4171. A generator produces electrical power of 40 kW, when operating at a voltage of 2 kV. The load is connected to the generator through a transmission line of resistance 10 \Omega.

a) How much power is dissipated during the transmission of electrical energy?

b) Find the efficiency of the transmission of electrical energy.

c) What are the above asked values if at both ends of the transmission lines an ideal transformer is used to step up or step down the voltage. Both transformers can step up or down the voltage by a factor of 10.

(4 points)

Deadline expired on 11 June 2009.

Statistics on problem P. 4171.
81 students sent a solution.
4 points:66 students.
3 points:3 students.
1 point:4 students.
0 point:6 students.
Unfair, not evaluated:2 solutions.

  • Problems in Physics of KöMaL, May 2009

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