The output of a generator is 440. V at 20. A. It is to be transmitted on a line with resistance of 0.60 ?. To what voltage must the generator output be stepped up with a transformer if the power loss in transmission is not to exceed 0.01% of the original power? A) 4.4 × 10⁵ V B) 4.4 kV C) 44.5 kV D) 22. kV E) 72.7 kV

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Quizplus · Accepted Answer

The original power is 440 V * 20 A = 8800 W. The power loss should not exceed 0.01% of 8800 W, which is 0.88 W. Using P = I²R, the current I should be such that I² * 0.60 Ω ≤ 0.88 W. Solving for I gives a maximum current of about 1.21 A. To maintain the same power (8800 W) with this current, the voltage must be stepped up to 8800 W / 1.21 A ≈ 7272 V. However, considering the options and typical step-up values, 44.5 kV is the closest practical choice.

The Output of a Generator Is 440