Suppose a motor connected to 117 V source draws 20.2 A when it first starts. (a) What is its resistance? (b) What current does it draw at its normal operating speed when it develops a 100 V back emf? c) The motor in a toy car operates on 6.20 V, developing a 3.00 V back emf at normal speed. If it draws 2.80 A at normal speed, what current does it draw when starting? A

Suppose a motor connected to 117 V source draws 20.2 A when it first starts. (a) What is its resistance? (b) What current does it draw at its normal operating speed when it develops a 100 V back emf? c) The motor in a toy car operates on 6.20 V, developing a 3.00 V back emf at normal speed. If it draws 2.80 A at normal speed, what current does it draw when starting? A

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter31: Faraday’s Law

Section: Chapter Questions

Problem 31.48P: A motor in normal operation carries a direct current of 0.850 A when connected to a 120-V power...

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