Two parallel conducting bars are joined at one end by a resistor with resistance R and separated by a distance d. Another conducting bar of length d slides at constant velocity v along the parallel bars. The bars have a negligible resistance. a) What is the expression of the current flow in the circuit? b) How much power is required to move the bar? c) How does the power dissipated in the resistance compare with the power required to move the bar? d) Explain how the motion of the moving bar affect the induced emf.

Two parallel conducting bars are joined at one end by a resistor with resistance R and separated by a distance d. Another conducting bar of length d slides at constant velocity v along the parallel bars. The bars have a negligible resistance. a) What is the expression of the current flow in the circuit? b) How much power is required to move the bar? c) How does the power dissipated in the resistance compare with the power required to move the bar? d) Explain how the motion of the moving bar affect the induced emf.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter13: Electromagnetic Induction

Section: Chapter Questions

Problem 61P: A 120-V, series-wound motor has a field resistance of 80 and an armature resistance of 10. When it...

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A 120-V, series-wound motor has a field resistance of 80 and an armature resistance of 10. When it is operating at full speed, a back emf of 75 V is generated, (a) What is the initial current drawn by the motor? When the motor is operating at full speed, where are (b) the current drawn by the motor, (c) the power output of the source, [ d) the power output of the motor, and (e) the power dissipated in the two resistances?
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