Middle Technical UniversitySubject: Electrical DC MachinesElectrical Engineering Technical CollegeStage:2ndDepartment of Automation and ControlTechnologies EngineeringDate: 13/2/2021Lecture: Ali Kadhem HamzahNote: Attempts to answer all questionsQI: Select the right answer for the following:1- If number of poles in a lap wounded generator is increased by a factor 2, thengenerated emf will:a) Increase by a factor of 4b) Remain samec) Increase by a factor 2d) Decrease by a factor 22- Which of the following accounts for smallest part of full load losses?a) Magnetic lossesb) Mechanical lossesc) Field copper lossd) Armature copper loss3- Efficieney of ad.c. shunt generator is maximum whena) Stray losses are equal to copper lossesb) Magnetic losses are equal to mechanical lossesc) Armature copper losses are equal to constant lossesd) Field copper losses are equal to constant losses4- With the increase of the winding of a d.c. generator, terminal voltage will:c) Remain samea) Decreaseb) Increased) None of these5- A single phase transformer has N = 200 turns ,N2 = 400 turns, connected to120 V D.C source voltage, the output voltage V2 will be:a) 240 V b)0 Vc) 120 V d) 360 v6- For ad.c. shunt generator if the load increases, the output current will bewhile the field current will bea) Increase,increase b) increase,decrease c)increase,constant d) both constant.7-In a transformer has specific iron loss, subjected to normal load. If the load has beendoubled, the iron loss willa) As same as normal load b) increase e) decrease by half d) doubled8- A shunt DC generator running at 1000 r.p.m. has generated as200 V. If the speedincreases by20%, the generated voltage will nearly:

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Answered: 1- If number of poles in a lap wounded…

1- If number of poles in a lap wounded generator is increased by a factor 2, then generated emf will: a) Increase by a factor of 4 b) Remain same c) Increase by a factor 2 d) Decrease by a factor 2

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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