A professor connects a resistor in parallel with an electric motor (a schematic of the circuit is given in the figure). Armature 750 2 50 mH 120V 100 V The purpose of the resistor in the circuit is to limit the voltage across the armature coils, if, for example, the motor is disconnected from its power supply while running. For the configuration shown, a 12.0 V DC motor has an armature with a resistance of 7.50 Q and an inductance of 450 mH, and assume the back emf in the armature coils is 10.0 V when the motor running at normal speed. Calculate the maximum resistance R (in 0) that limits the voltage across the armature to 79.0V when the motor is unplugged.

A professor connects a resistor in parallel with an electric motor (a schematic of the circuit is given in the figure). Armature 750 2 50 mH 120V 100 V The purpose of the resistor in the circuit is to limit the voltage across the armature coils, if, for example, the motor is disconnected from its power supply while running. For the configuration shown, a 12.0 V DC motor has an armature with a resistance of 7.50 Q and an inductance of 450 mH, and assume the back emf in the armature coils is 10.0 V when the motor running at normal speed. Calculate the maximum resistance R (in 0) that limits the voltage across the armature to 79.0V when the motor is unplugged.

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter29: Sources Of The Magnetic Field

Section: Chapter Questions

Problem 26P

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Similar questions

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