7) Short-circuit test on an induction motor cannot be used to determine:A. windage lossesB. copper lossesC. transformation ratioD. power scale of circle diagramE. All above8) The shape of the torque/slip curve of induction motor is:A. parabolaВ. һурerbolaC. rectangular parabolaD. straigth lineE. rectangular9) A brushless exciter used when the synchronous machine is:A. SmallB. LargeC. MediumD. Very smallE. All above10) If the capacitor of a single-phase motor is short-circuited:A. the motor will not startB. the motor will runC. the motor will run in reverse directionD. the motor will run in the same direction at reduced r.p.m.E. All above11) A centrifugal switch is used to dis- connect 'starting winding when motor has:A. run for about 1 minuteB. run for about 5 minutesC. picked up about 50 to 70 per cent of rated speedD. picked up about 10 to 25 per cent of rated speedE. picked up about 0 to 10 per cent of rated speed12)If starting winding of a single-phase induction motor is left in the circuit, it will:A. run fasterB. spark at light loadsC. draw excessive current and overheatD. run slowerE. spark at rated loads13)The capacitors used in single-phase capacitor motors have no:A. voltage ratingB. dielectric mediumC. polarity markingD. definite valueE. All above

7) Short-circuit test on an induction motor cannot be used to determine: A. windage losses B. copper losses C. transformation ratio D. power scale of circle diagram E. All above 8) The shape of the torque/slip curve of induction motor is: A. parabola B. hyperbola C. rectangular parabola D. straigth line E. rectangular 9) A brushless exciter used when the synchronous machine is: A. Small B. Large C. Medium D. Very small E. All above 10) If the capacitor of a single-phase motor is short-circuited: A. the motor will not start B. the motor will run C. the motor will run in reverse direction D. the motor will run in the same direction at reduced r.p.m. E. All above

7) Short-circuit test on an induction motor cannot be used to determine: A. windage losses B. copper losses C. transformation ratio D. power scale of circle diagram E. All above 8) The shape of the torque/slip curve of induction motor is: A. parabola B. hyperbola C. rectangular parabola D. straigth line E. rectangular 9) A brushless exciter used when the synchronous machine is: A. Small B. Large C. Medium D. Very small E. All above 10) If the capacitor of a single-phase motor is short-circuited: A. the motor will not start B. the motor will run C. the motor will run in reverse direction D. the motor will run in the same direction at reduced r.p.m. E. All above

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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