12. In This poat, we are going to share Multiple Choice Questions (MCQ) on AC Fundamentals for Electrical Engineering Students. None of The Above; Show Explanatory Answer . It is determined by averaging all the instant values of the electrical parameter. Purely Capacitive Circuit 5. 19. It indicates the maximum value. Answer: 2…Also Decreases Explanation:   Suppose, when Inductance (L) = 0.02H, XL = 2πfL = 2 x 3.1415 x 50 x 0.02 = 6.28 Ω, Z = √ (R2+XL2) = √ (102 + 6.282) = 11.8 Ω. (a) frequency (b) frequency and area of the core (c) flux density of the core material. Admittance: The Admittance is defined as the reciprocal of impedance just as conductance is the reciprocal of resistance i.e. Single phase power system schematic diagram shows little about the wiring of a practical power circuit. 201. Most lighting in urban centers is powered using single-phase alternative current. 3 phase induction motor. 7. 0.6 leading unity 0.8 leading Answera A capacitor start, capacitor run single phase induction motor is basically a ac series motor 2 phase induction motor 3 phase induction motor. In case of Inductive circuit, Frequency is _____Proportional to the inductance (L) or inductive reactance (X L). In inductive circuit, when inductive reactance XL increases, the circuit current decreases, but the circuit power factor also Decreases. In pure capacitive circuit, the power is __________? The relationship between Impedance (Z) and Admittance(Y) is ___________ ? There are two types of system available in electric circuit, single phase and three phase system.In single phase circuit, there will be only one phase, i.e the current will flow through only one wire and there will be one return path called neutral line to complete the circuit. 13. 2. ⇐ MCQ in AC Circuits Part 7 | REE Board Exam . S Bharadwaj Reddy November 3, 2016 November 3, 2017. Comment. For a straight conductor, the alternating current produces a magnetic flux, which is more at the centre compared to the surface. The phase difference between voltage and current wave through a circuit element is given as 30°. So if you put Cos 90 = 0→Then Power will be Zero (In pure capacitive circuit). So if the power in a single phase … Three Phase AC Circuits MCQ’s with explanation. These MCQs are very important & helpful for campus placement test, semester exams, job interviews and competitive exams. Answer: (3)…Both 1 & 2. The peak value of a sine wave is 200 V. Its average value is (a) 127.4 V (b) 141.4 V (c) 282.8 V (d)200V . (a) low power factor wattmeter (b) unity power factor wattmeter (c) frequency meter (d) any type of wattmeter. Most of the industry operates on 3-phase power instead of single phase. Please consider supporting us by disabling your ad blocker. question number 7 has been incorrectly interpreted here.
we know,
I=V/Xc
and Xc=1/(2*pi*f*C)
that makes f directly proportional to I. © www.yourelectricalguide.com/ mcq on single phase transformer. We can see that, When Capacitance (C) was 500µF, then circuit current were 18.56 A, and Circuit power factor was (Cos θ) = 0.84. Main Menu. Phasor Diagram is the representation of a sine wave using a single line rotating in counter-clockwise direction with a constant velocity. Basic Principles of Electrical Machines; ... MCQ; Programmable Logic … If Power factor = Cos θ = 1, it means that _____________. AC Circuits Multiple Choice Questions Question 1 What will happen to the current in this circuit as frequency increases? Definition of Single phase. In case of Inductive circuit,  inductance (L) is ___________Proportional to the  inductive reactance (XL). This is a sinusoidal current waveform, where the value of current at any point is given as: For a small segment of thickness dθ, the area would be:  idθ. A. (a) high eddy current losses (b) reduced magnetic leakage (c) negligibly hysteresis losses (d) none of the above. Dear..Did you check it properly…???? Thus series resonance is avoided in power systems. 6. Q Factor = 1/ Power Factor=1/Cosθ= Z/R    …    (Where Power Factor Cosθ = R/Z), If R is too small with respect to Reactance, Then Q factor = Z/R = ωL/R = 2πfL / R    …    (ωL/R = 2πf). The single phase requires two wires for completing the circuit, i.e., the conductor and the neutral. Purely Inductive Circuit 4. AC circuits are usually three-phase for electrical distribution and electrical transmission purposes. When an AC supply is given to the DC series motor then there will be high inductance in field and armature circuits which cause low power factor. EE Board Exam April 1990. Your email address will not be published. This test is Rated positive by 87% students preparing for Electrical Engineering (EE).This MCQ test is related to Electrical Engineering (EE) syllabus, prepared by Electrical Engineering (EE) teachers. in the world is in the form of three-phase AC circuits. Series AC Circuits MCQ Questions Answers Electrical Engineering Series AC Circuits Electrical Engineering MCQ Questions Answers 1) Impedance of an a.c. circuit is a ________________. A. Learn Single Phase Induction Motors MCQ questions & answers are available for a Electrical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. Answer Explanation ANSWER: R 1 + R 2 /K 2. For a series RLC circuit at resonance, the voltage drop across capacitive and inductive components is ——-. Leave a Comment / Uncategorized / By Ajay Sharma. Apparent Power, True Power, Reactive Power and Power Factor. Since the sinusoidal wave is symmetrical, the average value in the positive cycle would be equal to the average values in the negative cycle. MCQ No. This contains 20 Multiple Choice Questions for Electrical Engineering (EE) Test: Single Phase HW AC-DC - 1 (mcq) to study with solutions a complete question bank. Reading should be taken as it is b. Set 04. (a) Primary winding (b) Secondary winding (c) Low voltage winding (d) High voltage winding. The reactance of a transformer depends on (a) size of the core (b) size of the tank (c) leakage flux (d) all of the above. Leave a Comment Cancel reply. Get Free Android App | Download Electrical Technology App Now! The starting torque of a squirrel-cage induction motor is low negligible same as the full-load torque slightly more than full-load torque 3. A double squirrel-cage induction motor has two rotors moving in opposite direction two parallel windings in the stator two parallel windings in the rotor two series windings in the stator 2. AC Circuits Multiple Choice Questions Question 1 What will happen to the current in this circuit as frequency increases? 1. For the circuit given in question 6, assume the inductor is replaced by a capacitor of 75 microfarads. Q1. Single Phase AC Circuits MCQs ( With Explanatory Answers) 1. The  angle (θ) between Voltage and Current is Zero. A three-phase AC system consists of three-phase generators, transmission lines, and loads. In a split phase motor, the running winding should have (a) high resistance and low … Hence it is zero for a full cycle. Home » Single Phase Full Wave AC DC Converter MCQ Power Electronics MCQ Instrumentation Tools assists you with a complete guide of objective questions which mainly targets the aspirants of Electrical, Electronics and Instrumentation engineering Streams to crack the competitive exams and to prepare for the top MNC companies written tests. For More Detail : Q Factor in Electrical and Electronics Engineering. In a split phase motor, the running winding should have (a) high resistance and low inductance (b) low resistance and high inductance (c) high resistance as well as high inductance Since current is in phase with supply voltage, the total phase difference would be zero and hence XC = XL. And Cos θ = R/Z = the ratio between Resistance and Impedance = Resistance / Impedance = R / Z Also Cos θ = The Cosine of angle between Current and voltage = P = V I Cos θ. Answer:     2. 2. Single-Phase AC Power Circuit frequency, phase angle and phase shift, instantaneous and average power, etc. What is the inductance of the coil? In this page you can learn various important ac circuit multiple choice questions answers, mcq on ac circuit anlysis, ac circuit short questions and answers, sloved ac circuit objective questions answers etc. Single-phase motor MCQ - 1. Hence useful cross section of the conductor is lesser than the actual one and the effective resistance is higher. Projects. Q.196 Inductance L opposes changing in current during _____ A. stating interval B. transient interval C. normal D. any of the above Ans. Alternating current across a conductor is ———. The total power of a three-phase AC circuit is equal to three times the single phase power. Set 09. In case of Inductive circuit, Frequency is ___________ Proportional to the Current. 1. For the above circuit, the inductive reactance is given as: Substituting the values, f = 50 Hz, L = 0.1H, we get  = 31.4 Ohms approx. These are 75.48 ohms and 57.44 ohms respectively. نور الدين عبد الكريم ابراهيم الحمد
Welcome Dear. Now we increases Inductance (L) form 0.02 H to 0.04 H, XL = 2πfL= 2 x 3.1415 x 50 x 0.04 = 12.56 Ω, Z = √ (R2+XL2) = √ (102 + 12.562) = 16.05 Ω. Ques 44. Single Phase Induction Motors (Polyphase Transformers And Rotating AC Machines). SERIES CIRCUITS. Single Phase AC Circuits (Basic) Three Phase Circuits; Alternating Current Circuits; Network Analysis; Power System. 15. 1. which will improve your skill. Single phase power system schematic diagram shows little about the wiring of a practical power circuit. Thus current is more at the outer surface where the inductance is less. Answer.2. MCQ (Single Correct Answer) GATE EE 2008 In the single phase voltage controller circuit shown in the figure, for what range of triggering angle $$\left( \alpha \right)$$, the output voltage $$\left( {{V_0}} \right)$$ is not controllable? (a) become less with peaked wave shape of applied voltage (b) independent of the wave shape of the applied voltage (c) either of the above (d) none of the above. There are two types of system available in electric circuit, single phase and three phase system.In single phase circuit, there will be only one phase, i.e the current will flow through only one wire and there will be one return path called neutral line to complete the circuit. (A) 0° (B) 45° (C) 90° (D) 180° Correct Answer. Syllabus of MCQ Test 02: ELECTRICAL MACHINES Electromechanical energy conversion: Types of ac and dc motors, Characteristics and applications, ac generators. Xc = 1/2πfC ….(2)….. BEE: Sem I MCQ’s on Three phase circuits Date: / / Div: Roll no: Q1. Depicted above, is a very simple AC circuit.If the load resistor’s power dissipation were substantial, we might call this a “power circuit” or “power system” instead of regarding it as just a regular circuit. 64. (a) Hysteresis losses are reduced (b) Saving in winding material (c) Copper losses are negligible (d) Eddy current losses are totally eliminated. a. Explanation:As we know that power in single phase AC Circuits = P = VI Cos θ. Set 01. a) The saturation voltage V CF of silicon transistor is more than germanium transistor. 9. Comment. a. R 1 + R 2 /K 2 b. R 2 + R 1 /K 2 c. R 1 + K 2 R 2 d. R 2 + K 2 R 1. Choose the letter of the best answer in each questions. But, this is only possible when θ = 0 ( in case of Power factor = Cos θ). We are sure, this will help you to understand the complete concept of Active , … Single Phase A. C. Circuits. Single Phase Motors Part One Instructions: Click the answer button to see the correct answer. Power in a Three Phase Circuit = _. Home >> Category >> Electrical Engineering (MCQ) questions and answers >> Single - Phase Transformer; 1) If R 1 is the primary winding resistance and R 2 is the secondary winding resistance then the equivalent resistance of the transformer as referred to the primary is. How to Calculate/Find the Rating of Transformer in kVA (Single Phase and Three Phase)? 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 Contents: Introduction to Single Phase AC Circuit Purely Resistive Circuit Purely […] In this page you can learn various important energy meter multiple choice questions answers,mcq on energy meter with answers,mcq on energy meter,sloved energy meter objective questions answers, energy meter multiple choice questions answers etc. Nov 19, 2017 - Single Phase AC Circuits MCQs ( With Explanatory Answers) Electrical and Electronics mcqs, multiple choice questions and fill in the blanks with explanation Single phase induction motor can be made self-starting by a) Adding series combination of capacitor and auxiliary winding in parallel with the main winding b) Adding an auxiliary winding in parallel with the main winding c) Adding an auxiliary winding in series with a … – Examples in British and SI System, Thevenin’s Theorem. i.e ….. Xc ∞ 1/f Puttint (2) into (1) I = V/ (1/2πfC)…i.e ..I = V x 2πfC. 2. Theangle θ  between Voltage and Current is Zero Explanation: We know that Power factor = Cos θ  Given value of Power factor is = 1. Answer: (c) … ⇐ MCQ in AC Circuits Part 4 | REE Board Exam . No answer description required for this question. In case of Capacitive circuit, Frequency is ___________ Proportional to the Current. In a split phase motor, the running winding should have (a) high resistance and low inductance (b) low resistance and high inductance (c) high resistance as well as high inductance (d) low resistance as well as low inductiance Ans: b 2. mcq on single phase induction motor. Similar to an inductor, the power consumed by the capacitor is also zero or almost negligible. this guide covers three phase ac circuits multiple choice questions with answers and explanation. Explanation: Suppose, when Capacitive reactance (Xc) = 6 Ω, Now we increased Capacitive reactance = 10 Ω, Z = √ (R2+XC2) = √ (102 + 10 2) = 14.14 Ω. Reciprocal of Power Factor = _________? 1. Electrical Measurements. (a) size of the core (b) size of the tank (c) leakage flux (d) all of the above. A capacitor, an electric resistance heater, and impedance are connected in parallel to a 120 V, 60 Hz system. The capacitor draws 50 var, the heater draws 100 W and the impedance coil draws 269 VA at a pf 0f 0.74 lagging. (a) even harmonica in addition to fundamental (b) odd harmonics in addition to fundamental (c) both odd and even harmonics in addition to fundamental (d) none of the above. Generation; Transmission & Distribution; Switch Gear & Protection; Machines. Blogger Comment Facebook Comment. Introduction to Single Phase AC Circuit 2. In a split-phase motor, running winding have___ A. high resistance & low inductance B. low resistance & high inductance Learn Three Phase Systems In Power Applications MCQ questions & answers are available for a Electrical Engineering students to clear GATE exams, various technical interview, competitive examination, and another entrance exam. 351. Conceicao Rodrigues College of Engineering. For single phase supply frequency of 50 HZ, ripple frequency in full wave rectifier is . So in single phase minimum amount of power can be transported. Answer:          5. But, when we increased Circuit Capacitance from 500µF to 1000µF, then current also increased from18.56 A to 21A, also Power Factor (Cos θ) increased from 0.84 to 0.95. 2. Consider the sinusoidal alternating current signal given below. Syllabus of MCQ Test 02: ELECTRICAL MACHINES. So if you put Cos 90 = 0→Then Power will be Zero. We are working on it. (a) the current on secondary side is negligible (b) the voltage on secondary side does not vary (c) the voltage applied on primary side is low (d) full-load current is not supplied to the transformer. 1. (a) Step-up transformer (b) Step-down transformer (c) Potential transformer (d) Current transformer. So in single phase minimum amount of power can be transported. For explanatory answer, click on the toggle button labeled as “check explanatory answer”.