Q6: Choose the correct answer, (answer five only): 1-The slip-rings in an AC gen.provide means of: (a)connecting an external circuit to a rotating armature inding ((b) periodically reversing the current produced by an armature winding (c) supporting a rotating armature without the need for bearings 2-The rotor of an AC induction motor consists of: ((a) a single copper loop which rotates inside the field created by a permenent magnet (b)aseries of coil windings on a laminated iron core with connections via slip-rings (c) aliminated iron core inside a squirrel cage made from copper or aluminuim 3-In a balanced star-connected three-phase system the line evurrent is a 2 A and the lin voltage is 220 V.If the power factor 0.75 which one of the folowing gives the total powe in the load? (a)520W ((b)271W (c)900W 4-E, for a shont d.c gen.is.... (a)V₁-1,Ra (b)V₁-L(R+R) (c)V₁¹1₂R₂ 5-The induced e.m.f. in DC gen. depends on: (a)field coil (b)current

Q6: Choose the correct answer, (answer five only): 1-The slip-rings in an AC gen.provide means of: (a)connecting an external circuit to a rotating armature inding ((b) periodically reversing the current produced by an armature winding (c) supporting a rotating armature without the need for bearings 2-The rotor of an AC induction motor consists of: ((a) a single copper loop which rotates inside the field created by a permenent magnet (b)aseries of coil windings on a laminated iron core with connections via slip-rings (c) aliminated iron core inside a squirrel cage made from copper or aluminuim 3-In a balanced star-connected three-phase system the line evurrent is a 2 A and the lin voltage is 220 V.If the power factor 0.75 which one of the folowing gives the total powe in the load? (a)520W ((b)271W (c)900W 4-E, for a shont d.c gen.is.... (a)V₁-1,Ra (b)V₁-L(R+R) (c)V₁¹1₂R₂ 5-The induced e.m.f. in DC gen. depends on: (a)field coil (b)current

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

See similar textbooks

Similar questions

1- The compole is used to 2- A 4-pole wave winding machine has ------ magnetic circuit. 3- A commutator pitch for the duplex wave winding is equal to - 4- A 2-pole triplex lap winding will have parallel paths. 5- A 6-pole lap wound generator has 900 conductors. The e.mf induced per one turn being 3V. the generated voltage of the grnerator is ( 6-A 10kW, 250 V shunt generator has armature and field resistance of 0.2 and 502 respectively. Then the generated voltage is and
DEGREE: ELECTRICAL ENGINEERING SUBJECT/COURSE: AC MACHINES Answer the following questions (A, B and C) depending on the topic. 1. ALTERNATORS A. Why is it necessary to maintain the speed of an alternator at all times and how do they control the speed of an alternator when in operation? B. Distinguish between half-coiled and full-coiled armature windings in alternators. C. Why are fractional pitch windings generally used in alternators?
Which of the following statements about three-phase induction motor is false (A) The speed of rotation of the magnetic field is called the synchronous speed. (B) A three-phase supply connected to the rator produces a rotation magnetic field. (C)The rotating magnetic field has a constant speed and constant magnitude. (D) It is essentially a constant speed type machine.
Name three factors that determine the torque produced by an induction motor.
2) the armature windings of a 12-pole DC machine are composed of 72 coils with 10 windings, and the windings are 5the layered wave is yellowish. The Rotor speed is 1000 rpm and the flux value per pole is 25mWb.Resistance of Armature windings, commutation windings and compensation windings is 70mΩ, 10mΩ and5mω. (d) calculate the voltage value induced in the machine. (e) DC machine as a foreign (external) excitation generator with a rated current of 100A at full loadif it is started, what is the terminal voltage value? Calculate. (Enter the formulas that you use for calculations and enter the names of the corresponding parameters.)
Electrical Engineering Consider a balanced 3-phase current flowing into the stator of a 2-pole induction motor. What should be the current expressions for a clockwise rotation of the magnetic field? For wt = 10, 100,200,300 show that the rotating magnetic field is actually rotating clockwise using stator conductor
21 The armature shown in the following figure has 81 slots, and the commutator has 243 segments. It will be wound to give a 6-pole lap winding having 1 turn per coil. If the flux per field pole is 30 mWb, calculate the following: a. The induced voltage at a speed of 1200 r/min b. The average flux density per pole c. The time needed to reverse the current in each armature coil, knowing that the brushes are 15 mm wide and that the diameter of the commutator is 450 mm
Consider the following statements regarding the design of the distributed armature winding in a three-phasealternator:1. It reduces the phase belt harmonics.2. It increases utilization of armature iron and copper.3. It increases rigidity and mechanical strength of the winding.4. It reduces copper in the overhand of the winding. Which of the statements are correct? a. 1,3 and 4b. 2,3 and 4c. 1,2 and 3d. 1,2,3 and 4
2- A 4-pole, wave-wound d.c. shunt generator has an armature winding consisting of 300 turns each of 0.0020. The armature resistance is a) 0.152 b)0.62 c) 0.30 d) none of above
A 8 pole wave wound dc shunt generator runs at a speed of 900 rpm, has an armature and shunt field resistance of 0.7 N and 300 N respectively. The armature has 960 conductors and flux per pole is 0.057 Weber. If the lamp load connected has a resistance of 60 2, determine (i) Generated EMF, (ii) Total Resistance, (iii) Armature Current, (iv) Terminal Voltage. Generated EME (Eg) Total Resistance (Rt) Armature Current (la) Terminal Voltage (V)
Q choose the correct answer: 1-Brushless excitation system consisting of.... a- Stator field winding and power diodes b-stator and rotor field winding and capacitor c- stator and rotor field winding and capacitor d- Everything mentioned in the options 2- Voltage generated per phase in an alternator is proportional to a- Flux per pole b- Number of turns in armature c-Winding factors d- Everything mentioned in the options e- Frequency of waveform 3- If input mech. Power of SG constant, the functionality of AVR is a- Control flux of rotor b-Control terminal voltage c- Control flux and terminal voltage d-Control Load angle
(B)-ndicate whether the following statements are true or false and correct the faise statements. -When a series d.c. motor is operate without load, the armature will not run. The strength of magnetic field in d.c. shunt generator can be varied by varying the polarity of the field poles The main disadvantage of series generators is Output voltage varies as the Toad varies There is no output from the transformer under short-circuit conditions