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Home >> Category >> Electrical Engineering (MCQ) questions and answers >> Synchronous Machines; 1) Generally, in alternator divided winding rotor is preferred to a conventional winding rotor, because it gives. 130 TOP DC MOTOR Objective Questions Answers pdf free Download. 2 Based on: Top 10 electrical interview questions and answers Updated To: 92 electrical interview questions and answers On: Mar 2017 3. What is the purpose of yoke in d.c machine? Elementary DC Machines • The armature winding of a dc generator is on the rotor with current conducted from it by means of carbon brushes. Answer 1. 10. shaft . Multiple Choice Questions with Answers on DC Generators - Set 08 MCQ DC Generators Edit Practice Test: Question Set - 08. machines, and these appear somewhat more complicated but in reality are combi-nations of the three basics. • In a dc machine, the armature winding is found on the rotating member, referred to as the rotor. C. 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Synchronous Machines - Electrical Engineering (MCQ) questions and answers. At the start of the question, you are given a reasonable amount of data about a specific operating condition. C and D only 3. 3 This ebook consists of two parts: - Part I: 92 electrical interview questions and answers (pdf, free download) - Part II: … This is a tricky question. The Chapters of Multiple Choice Questions (MCQs) on DC Machines. The stator is stationary in space by definition and therefore so is its current. Laminations of core are generally made of (a) case iron (b) carbon (c) silicon steel (d) stainless steel Ans: c The armature of DC machine is made up of laminated sheets to ..... A. Poles. Solution. Tell me about your worst boss. DC Motor or Direct Current Motor Multiple Choice Questions and Answers. Electrical Engineering Questions with Answers pdf :-1. 1.It acts as a protecting cover for the whole machine and provides mechanical support for the poles. 4. Electric Motors are the machines that convert electrical energy into the mechanical energy which further is used to drive a vehicle, plant and many more things around us. Thread: Important Questions On Electrical Machines PDF Download. Current Electricity 2. A DC motor is a mechanically commutated electric motor powered from direct current (DC). Inertia, on the other hand, is a characteristic of matter — it is the resistance of mass to being in motion or removed from motion. For example, we have covered, the working principle of dc motors and working principle of dc generators. a) Will run at normal speed b) Will not run c) Will Run at lower speed d) Burn due to heat produced in the field winding View Answer. 9. bearings. Synchronous Machine Structures Stator and Rotor The armature winding of a conventional synchronous machine is almost invariably on the stator and is usually a three phase winding. Total 28 Questions have been asked from DC Machines: Separately Excited, Series and Shunt, Motoring and Generating Mode of Operation and Their Characteristics, Starting and Speed Control of DC Motors topic of Electrical Machines subject in previous GATE papers. On the other hand, the bus impedance matrix is equally well favored for power system fault analysis. A Single-phase autotransformer is a single winding transformer in which a part of the winding is common to both high-voltage and low-voltage sides. Brushes. The current in the rotor is switched by the commutator to also be stationary in space. What will happen if the back e.m.f. The bus admittance matrix is widely used for power-flow analysis. These objective type Electrical Machines questions are very important for campus placement test, semester exams, job interviews and competitive exams like GATE, IES, PSU, NET/SET/JRF, UPSC and diploma. Dear Readers, Welcome to Electrical Machines multiple choice questions and answers with explanation. Pick a real example (make sure it’s not about someone working in the company you want to join), but be discreet about the person’s identity. • The field winding is on the stator and is excited by direct current. Slip When Nr=Ns A)1 B)0 C)0.5 D)0.4. Magnetic frame or yoke. A list of top frequently asked Electrical Machines interview questions and answers are given below. 1. 50 Common Interview Questions and Answers Page 8 of 25 9. Network Admittance and impedance matrices . 75. a. 8. • Coils are placed in the slots. What is the difference between earth resistance and earth electrode resistance? Network Theorems 3. D only 2. 7. interpoles . This question is similar to many DC machine questions and falls into two parts. Latest D.C. Generators Interview Questions and Answers List 1. 6. armature windings. Electrical Engineering : Dc Motors QUESTIONS AND ANSWERS :: part1 : 1 to 5. Electrical4U’s MCQs are in a wide range of electrical engineering subjects including analog and digital communications, control systems, power electronics, electric circuits, electric machines – and much more. Following Electrical Engineering Multiple choice objective type questions and answers will help you in BSNL JTO, GATE 2020 and IES 2020 examinations : 1.In a D.C. shunt motor, speed is. Your name: Your Email: Your Comments: … Here are the types of questions on electric motors which are asked in an interview, question papers and other competitive exams as well. (b) A commutator is necessary as part of a DC generator to produce unidirectional voltage at the terminals of the generator (c) The field winding of a DC machine is housed in slots on the armature (d) The brushes of a DC machine are usually made of carbon and do not rotate with the armature Options: 1. D. Increase dissipation of heat from the armature surface View Answer . 3/23/2007 ELEC A6 DC Machine 9 DIRECT CURRENT MACHINES DC machine Construction • The rotor iron core is mounted on the shaft. 3. Explanation: In full pitched coils, as one conductor of a turn in a coil cuts N pole, the other conductor of the same turn cuts S pole resulting in the production of induced emf(E), i.e phase angle is 180 degree of a D.C. motor vanishes suddenly? This is how the relative angle between the stator and rotor magnetic flux is maintained near 90 degrees, which generates the maximum torque. CLICK HERE —-> EEE INTERVIEW QUESTIONS. 18. Popular topic for study. 5. pole shoes. This list is mainly about Multiple Choice Questions (MCQs) on DC Machines. Below are the list of all Electrical Engineering Multiple Choice Questions and Answers for EEE students. The topics that are covered in this PDF containing Electrical Machines Year GATE Solved Questions are: Single phase transformer: equivalent circuit, phasor diagram, open circuit and short circuit tests, regulation and efficiency; Three phase transformers: connections, parallel operation; Auto‐transformer, Electromechanical energy conversion principles, DC machines: separately excited, … Answer: Only one of the terminals is evident in the earth resistance. No-load speed of which of the following motor will be highest? So, we have covered all the possible sections of dc machines. Specially developed for the Electrical Engineering freshers and … How and why the compensating winding in dc machine excited? Important Questions On Electrical Machines PDF Download; Results 1 to 6 of 6 . Professionals, Teachers, Students and Kids Trivia Quizzes to test your knowledge on the subject. Dec 21, 2016 - Electrical Machines Objective Type Questions and Answer-PDF for Competitive Exams,electric dc machines motor mcqs questions and answers To reduce the Harmonic in generated EMF. Next » This set of DC Machines Multiple Choice Questions & Answers (MCQs) focuses on “DC Motor Basics -1”. also we can provide Electrical objective questions books & Interview questions. ANSWER:B 23. Q. The changes that take place in winding elements during the period of short circuit by a brush is called commutation. 21. >The presence of back emf (Eb) or counter emf makes the dc motor a self regulating machine, i.e. 123 TOP D.C. Motors - Electrical Engineering Multiple Choice Questions and Answers So answer it with a mix of honesty, diplomacy and positivity. In this chapter, we concentrate on conventional synchronous machines whereas the brushless dc motors will be discussed later in a separate chapter.