20. A mechanical connection between machines is NOT needed for loading back A. induction machines. B. synchronous machines. C. d-c shunt-wound machines. D. d-c series-wound machines. 21. A synchronous motor is being tested for efficiency. If an auxiliary motor is needed for the test procedure, the method applied is the A. mechanical input method. B. calorimeter method. C. electrical input method. D. retardation method.

20. A mechanical connection between machines is NOT needed for loading back A. induction machines. B. synchronous machines. C. d-c shunt-wound machines. D. d-c series-wound machines. 21. A synchronous motor is being tested for efficiency. If an auxiliary motor is needed for the test procedure, the method applied is the A. mechanical input method. B. calorimeter method. C. electrical input method. D. retardation method.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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