A step-up transformer is designed to have an output voltage of 2 200 V (rms) when the primary is connected across a 110-V (rms) source. (a) If the primary winding has exactly 78 turns, how many turns are required on the secondary? turns (b) If a load resistor across the secondary draws current of 1.70 A, what is the current in the primary, assuming ideal conditions? A (c) If the transformer actually has an efficiency of 97.0%, what is the current in the primary when the secondary current is 1.20 A?

A step-up transformer is designed to have an output voltage of 2 200 V (rms) when the primary is connected across a 110-V (rms) source. (a) If the primary winding has exactly 78 turns, how many turns are required on the secondary? turns (b) If a load resistor across the secondary draws current of 1.70 A, what is the current in the primary, assuming ideal conditions? A (c) If the transformer actually has an efficiency of 97.0%, what is the current in the primary when the secondary current is 1.20 A?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter15: Alternating-current Circuits

Section: Chapter Questions

Problem 44P: A step-up transformer is designed so that the output of its secondary winding is 2000 V(rms) when...

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