1-Which of the following load normally need starting torque more than the rated torque?© Centrifugal pump(a) Conveyors2-The efficiency of the DC motor at maximum power is(b) Blowers(d) Air compressor(a) 90%(b) 100%© Around 80%(d) Less than 50%3-in which of the following applications DC series motor is used?(a) Centrifugal Pump(b) Motor Operation in DC and AC© Water pump drive(d) Starter for car4-Which DC motor has the least percentage increase in Input current for the same percentageincrease in torque?(a)Separately excited motor(b)Series motor© Shunt motor ( d)Compound motor5-Counter EMF of the DC motor is(b)More than the applied voltage(a) Less than the applied voltage© Equal to the applied voltage6-Which DC motor is used for the conveyor?(d)None of the above(a)Series motor (b)Cumulative compound motor(c) Differentially compound motor(d)Shuntmotor7-Which D.C motor is preferred for machine tools?(a) Series motor(b)Cumulative compound motor (c) Differentially compound motor(d)Shunt motor8-When the speed of D.C motor is increased(a)Back E.M.F increases and current drawn decreases (b) Back E.M.F decreases and current drawnincreases© Back E.M.F and current drawn both increases (d)Back E.M.F and current drawn both decreases9-A 240v de shunt motor with an armature resistance of 0.5 has a full load current of 40A.Find out the ratio of the stalling torque to the full load torque when a resistance of 1 ohm isconnected in series with the armature(a)12(b) 6© 4(d)1010-A DC Motor is driving a constant load torque having armature resistance of 0.15 2 andarmature current of 0.25 A having connected to a voltage of 230 V. Now a resistance of 1 ohmis added into the armature circuit. The ratio of their speed will be(a)0.25(b)1.24©0.62(d)0.7211-220 V, 15 kW, 1000 RPM shunt Motor with an armature resistance of 0.252, has a ratedline current of 68 A and a rated field current of 2.2 A. The change in field flux required toobtain a speed of 1600 RPM while drawing a line current of 52.8 A and a field current of 1.8 Ais(a)18.18% Increase(b)18. 18% decrease©36.36 % increase(d)36. 36 % decrease

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1-Which of the following load normally need starting torque more than the rated torque? (a) Conveyors (b) Blowers © Centrifugal pump (d) Air compressor 2-The efficiency of the DC motor at maximum power is |(a) 90% (b) 100% © Around 80% (d) Less than 50% 3-in which of the following applications DC series motor is used?

1-Which of the following load normally need starting torque more than the rated torque? (a) Conveyors (b) Blowers © Centrifugal pump (d) Air compressor 2-The efficiency of the DC motor at maximum power is |(a) 90% (b) 100% © Around 80% (d) Less than 50% 3-in which of the following applications DC series motor is used?

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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