Last Answer : In repulsion motor, maximum torque is developed when brush axis is at 45° electrical to the field axis.
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116 views
1 answer
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Mar 20, 2018
by
anonymous

Last Answer : The repulsion-start induction-run motor is used because of high starting torque.
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89 views
1 answer
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Mar 20, 2018
by
anonymous

In a double squirrel cage induction motor, good starting torque is produced as (A) Large current flows through the outer high resistance winding. (B) Large current flows through the inner high ... the outer high resistance winding. (D) Large current flows through the inner low resistance winding.
Last Answer : In a double squirrel cage induction motor, good starting torque is produced as Large current flows through the outer high resistance winding.
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136 views
1 answer
asked
May 8, 2018
by
anonymous

Torque developed by a three-phase, 400V, induction motor is 100 N -m. If the applied voltage is reduced to 200-V, the d'veloped torque will be
Last Answer : Torque developed by a three-phase, 400V, induction motor is 100 N -m. If the applied voltage is reduced to 200-V, the d'veloped torque will be 25 N -m
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422 views
1 answer
asked
Apr 29, 2018
by
anonymous

The torque developed by any 3-phase induction motor at 0.8 p.u. slip is (A) Full-load torque (B) unstable torque (C) starting torque (D) break down
Last Answer : The torque developed by any 3-phase induction motor at 0.8 p.u. slip is unstable torque
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3.1k views
1 answer
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Apr 28, 2018
by
anonymous

Last Answer : Capacitor start motor has high torque in starting
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133 views
1 answer
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Sep 13, 2017
by
anonymous

Last Answer : For the same H.P. rating and full load speed, following motor has poor starting torque differentially compounded.
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164 views
1 answer
asked
Mar 20, 2018
by
anonymous
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Last Answer : In repulsion motor, zero torque is developed when brush axis coincides with the field axis and brush axis is 90° electrical to field axis.
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97 views
1 answer
asked
Mar 20, 2018
by
anonymous

The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque (1) Decreases (2) Increases (3) Remains constant (4) None of the above
Last Answer : The speed of a three-phase induction motor is controlled by variable voltage variable frequency control (i.e. keeping V/f constant). As the frequency is reduced, the slip at maximum torque Increases
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234 views
1 answer
asked
May 1, 2018
by
anonymous

speed control methods of three phase induction motor?
Last Answer : Speed control of three phase induction motor
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363 views
2 answers
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Aug 9, 2017
by
anonymous

Last Answer : A repulsion motor is equipped with commutator.
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123 views
1 answer
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Mar 20, 2018
by
anonymous

Last Answer : The purpose of stator winding in the compensated repulsion motor is to improve power factor and provide better speed regulation.
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110 views
1 answer
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Mar 20, 2018
by
anonymous

The synchronous speed of an 8 pole induction motor supplied power from a 50 Hz source will be ?
Last Answer : Ns equals f/pair pole 50/4 - 12.5
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202 views
2 answers
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Dec 31, 2017
by
anonymous

Last Answer : In repulsion motor direction of rotation of motor is the same as that of brush shift.
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116 views
1 answer
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Mar 20, 2018
by
anonymous

In an induction motor if the flux density is reduced to one-half, of its normal value then the torque will (1) reduce to one-half (2) reduce to one-fourth (3) remain unchanged (4) increase four times
Last Answer : In an induction motor if the flux density is reduced.to one-half, of its normal value then the torque will reduce to one-fourth
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371 views
1 answer
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May 1, 2018
by
anonymous

Last Answer : The armature torque of the D.C. shunt motor is proportional to armature current.
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210 views
1 answer
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Mar 20, 2018
by
anonymous

Last Answer : The torque produced in induction type relay (shaded pole structure) is inversely proportional to the square of the current.
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829 views
1 answer
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Mar 20, 2018
by
anonymous

A 3-phase, 4-pole, 50Hz induction motor runs at a speed of 1440 rpm. The rotating field produced by the rotor rotates at a speed of ________ rpm with respect to stator field. (A) 1500 (B) 0 (C) 1440 (D) 60
Last Answer : 0
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2.0k views
2 answers
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Apr 28, 2018
by
anonymous

In a 3-phase slip-ring induction motor, the slip at some speed is 0.05. The speed is reduced by inserting an external resistance in the rotor circuit and the slip is 0.15. If the rotor winding resistance per phase is 0.2 Ω, the external resistance is (A) 0.2 Ω (B) 0.3 Ω (C) 0.4 Ω (D) 0.5 Ω
Last Answer : In a 3-phase slip-ring induction motor, the slip at some speed is 0.05. The speed is reduced by inserting an external resistance in the rotor circuit and the slip is 0.15. If the rotor winding resistance per phase is 0.2 Ω, the external resistance is 0.3 Ω
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165 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : For constant torque drive armature voltage control speed control method is preferred.
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177 views
1 answer
asked
Mar 20, 2018
by
anonymous

Split phase induction motor
Last Answer : Split phase induction motor : There are two windings used in split phase induction motor. It is a type of single-phase induction motor. There are two winding one is called main winding and ... motor have low starting torque it is used for small fans, blowers, centrifugal pumps, grinders etc.
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230 views
1 answer
asked
Sep 20, 2018
by
anonymous

A change of 4% in the supply voltage to an induction motor will produce a change of approximately
Last Answer : A change of 4% in the supply voltage to an induction motor will produce a change of approximately 8% in the rotor torque
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467 views
1 answer
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May 8, 2018
by
anonymous

The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is
Last Answer : The slip of 400 V, three phase, 4 -pole induction motor when rotating at 1440 rpm is 4 percent
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361 views
1 answer
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Apr 29, 2018
by
anonymous

A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for
Last Answer : A 400 V, 50 Hz three-phase induction motor rotates at 1440 rpm on full -load. The motor is wound for 4 poles
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304 views
1 answer
asked
Apr 29, 2018
by
anonymous

In a split-phase induction motor, the resistance/reactance ratios of windings are such that (A) current in the auxiliary winding leads the current in the main winding (B) current in the ... (C) both windings develop the same starting torque (D) both windings develop high starting current
Last Answer : In a split-phase induction motor, the resistance/reactance ratios of windings are such that current in the auxiliary winding leads the current in the main winding
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106 views
1 answer
asked
Apr 28, 2018
by
anonymous

In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then (A) the flux is constant (B) the flux first decreases and then increases in ... increases and decreases in the opposite direction with the same magnitude (D) current flows through the rotor
Last Answer : In a single-phase induction motor when the rotor is stationary and voltage is applied to the stator, then the flux first decreases and then increases in the same direction
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95 views
1 answer
asked
Apr 28, 2018
by
anonymous
.jpg)
An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is (A) 5.06 kW (B) 0.3 kW (C) 100 kW (D) 83.33 kW
Last Answer : An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is 83.33 kW
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179 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : Reason is kinetic energy
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285 views
2 answers
asked
Mar 20, 2018
by
anonymous

Last Answer : If starting winding of a single-phase induction motor is left in the circuit, it will draw excessive current and overheat.
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234 views
1 answer
asked
Mar 20, 2018
by
anonymous
.jpg)
Last Answer : If a single phase induction motor runs slower than normal, the most likely defect is worn bearings.
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170 views
1 answer
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Mar 20, 2018
by
anonymous

Last Answer : The rotor slots, in an induction motor, are usually not quite parallel to the shaft because it helps in reducing the tendency of the rotor teeth to remain under the stator teeth.
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146 views
1 answer
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Mar 20, 2018
by
anonymous

How is a three phase cage induction motor self starting?
Last Answer : Any type of induction motor is self starting. Because the reason for torqe production require two flux displaced by some angle theta.If theta is constant with time then torqe will be constant;if ... torqe also pulsating. In induction motor this angle theta is not pulsating.so it is self starting
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158 views
1 answer
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Mar 17, 2018
by
anonymous

How does a single phase induction motor work?
Last Answer : As we know that single phase induction is not self started because for self started we require atleast two revolving field but single phase induction motor has only one. So we provide extra ... 1phase IM classified as split phase IM, capacitor start capacitor run, capacitor start induction run.
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124 views
1 answer
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Mar 17, 2018
by
anonymous

Is induction motor is self starting?
Last Answer : Single phase induction motor is not self starting. Three phase induction motor is self starting.
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111 views
1 answer
asked
Mar 17, 2018
by
anonymous

What is the definition of induction motor?
Last Answer : its working on magnetic base made by coils and its work with 1 phase or 3 phase ac or dc supply
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123 views
1 answer
asked
Mar 17, 2018
by
anonymous

What is the function of induction motor?
Last Answer : while you give supply to motor its motor run on magnet base
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158 views
1 answer
asked
Mar 17, 2018
by
anonymous

At which time power factor of the induction motor is low?
Last Answer : The power factor of the inducction motor is low at the time of starting as compare to while the induction motor is running.
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150 views
1 answer
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Mar 3, 2018
by
anonymous

What is mean by plugging in three phase induction motor?
Last Answer : Plugging in three-phase induction motor means interchanging of any two phases of a stator for quick stopping.
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153 views
1 answer
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Mar 3, 2018
by
anonymous

explain the working of single phase induction motor.
Last Answer : Stator has two winding namely main winding and auxiliary winding.when single phase ac supply is given to the motor,its produces alternating field.this field cut by a cage rotor.so some emf ... due to this emf,rotor flux produced.the interaction between two fluxes produce torque.so rotor rotates.
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186 views
1 answer
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Oct 24, 2017
by
anonymous

Last Answer : Induction motor is a AC motor it is also known as asynchronous motor .
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98 views
1 answer
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Sep 9, 2017
by
anonymous

Last Answer : if induction motor rotates exceed than its synchronous speed, it acts as a generator.
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67 views
1 answer
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Sep 9, 2017
by
anonymous

Induction motor
Last Answer : Induction Motor Inductor is a coil of wire which possess the property of inductance. Inductance is the property of an electric conductor which generate electromotive force (EMF ... motor are classified as slip ring induction motor and squirrel cage induction motor.
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77 views
1 answer
asked
Aug 9, 2017
by
anonymous

Single Phase Induction Motor
Last Answer : Single Phase Induction Motor Single phase induction motor is mostly used in home, office, shop and many single phase appliances like pumps, ... torque and silent operation. It is uses where silent operation is required.
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528 views
1 answer
asked
Aug 9, 2017
by
anonymous

DC motor gross torque example
Last Answer : .embed-container { position: relative; padding-bottom: 56.25%; height: 0; overflow: hidden; max-width: 100%; } .embed-container iframe, .embed-container object, .embed-container embed { position: absolute; top: 0; left: 0; width: 100%; height: 100%; }
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145 views
2 answers
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Apr 24, 2020
by
anonymous

Last Answer : Torque developed by a D.C. motor depends upon magnetic field, active length of the conductor, current flow through the conductors, number of conductors, radius of armature.
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638 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : A synchronous motor can develop synchronous torque at synchronous speed.
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114 views
1 answer
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Mar 20, 2018
by
anonymous

The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?
Last Answer : The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as pull-in torque.
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302 views
1 answer
asked
Mar 20, 2018
by
anonymous

The maximum torque which a synchronous motor will develop at rest for any angular position of the rotor, at rated stator supply voltage and frequency, is known as?
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106 views
0 answers
asked
Mar 20, 2018
by
anonymous

What is the maximum value of torque angle in synchronous motor?
Last Answer : The maximum value of torque angle in synchronous motor is 90 degrees electrical.
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1.5k views
1 answer
asked
Mar 18, 2018
by
anonymous

Why a dc series motor has a high starting torque?
Last Answer : motor
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86 views
1 answer
asked
Mar 15, 2018
by
anonymous
