1. The magnitude of the resultant flux in three phase supply system is equal to(a) Pm(b)(c)(d) Фт2. A three phase induction motor is wound for 4 poles and is supplied from 50-Hz system when slip is4%, the rotor speed will be(а) 1440 грm(b) 1445(c) 1450(d) 14553. Rotor resistance control method of speed control is used for(a) Squirrel-cage induction motors only.(b) Slip ring induction motors only.(c) Both (a) and (b).(d) None of the above.4. A 6-pole, 50-Hz, 3-o induction motor is running at 950 rpm and has rotor Cu loss of 5 kW. Itsrotor input is ..kW.(а) 100(b) 10(c) 95(d) 5.3.5. In a capacitor start motor, the phase displacement between starting and running winding can benearly(a) 10°(b) 30°(c) 60°(d) 90°6. A centrifugal switch is used to disconnect 'starting winding when motor has(a) run for about 1 minute(b) run for about 5 minutes(c) picked up about 50 to 75 per cent of rated speed(d) picked up about 10 to 15 per cent of rated speed7-Which of the following motors is usually used in house-hold refrigerators(a) D.C. shunt motor(b) D.C. series motor (c) Single phase induction motor (d) Reluctance motor8- The DC test for three phase induction motor determines(a) Rotor resistance(R2) (b) Stator reactance(X1) (c) Stator resistance(R1)(d) Rotor reactance(X2)

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1. The magnitude of the resultant flux in three phase supply system is equal to (a) Pm (b)m (d) Фт 2. A three phase induction motor is wound for 4 poles and is supplied from 50-Hz system when siip is 4%, the rotor speed will be (а) 1440 грm (b) 1445 (с) 1450 (d) 1455 3. Rotor resistance control method of speed control is used for (a) Squirrel-cage induction motors only. (b) Slip ring induction motors only. (c) Both (a) and (b). (d) None of the above. 4. A 6-pole, 50-Hz, 3-o induction motor is running at 950 rpm and has rotor Cu loss of 5 kW. Its rotor input is ...kW. (a) 100 (b) 10 (c) 95

1. The magnitude of the resultant flux in three phase supply system is equal to (a) Pm (b)m (d) Фт 2. A three phase induction motor is wound for 4 poles and is supplied from 50-Hz system when siip is 4%, the rotor speed will be (а) 1440 грm (b) 1445 (с) 1450 (d) 1455 3. Rotor resistance control method of speed control is used for (a) Squirrel-cage induction motors only. (b) Slip ring induction motors only. (c) Both (a) and (b). (d) None of the above. 4. A 6-pole, 50-Hz, 3-o induction motor is running at 950 rpm and has rotor Cu loss of 5 kW. Its rotor input is ...kW. (a) 100 (b) 10 (c) 95

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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