A large power plant generates electricity at 12.0 kV. Its old transformer once converted the voltage to 376 kV. The secondary of this transformer is being replaced so that its output can be 501 kV for more efficient cross-country transmission on upgraded transmission lines. (a) What is the ratio of turns in the new secondary to turns in the old secondary? Ns, new Ns, old (b) What is the ratio of new current output to old output (at 376 kV) for the same power? Is, new = Is, old (c) If the upgraded transmission lines have the same resistance, what is the ratio of new line power loss to old? P new Pold

A large power plant generates electricity at 12.0 kV. Its old transformer once converted the voltage to 376 kV. The secondary of this transformer is being replaced so that its output can be 501 kV for more efficient cross-country transmission on upgraded transmission lines. (a) What is the ratio of turns in the new secondary to turns in the old secondary? Ns, new Ns, old (b) What is the ratio of new current output to old output (at 376 kV) for the same power? Is, new = Is, old (c) If the upgraded transmission lines have the same resistance, what is the ratio of new line power loss to old? P new Pold

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter25: Electromagnetic Induction

Section: Chapter Questions

Problem 60A

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