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Answer :

The speed of a universal motor is usually reduced by using gearing.

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Last Answer : The speed of a universal motor is generally reduced by using gear trains.

Last Answer : Speed control of a universal motor is achieved by varying field flux with tapped field windings, connecting rheostat in series, applying variable voltage by means of silicon controlled rectifier, applying variable voltage by means of variable auto-transformer.

Last Answer : The speed/load characteristics of a universal motor is same as that of D.C. series motor.

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Description : State working principle of universal motor with the help of diagram.

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Description : State two applications of 1) Shaded pole motor 2) Universal motor

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Description : Draw and explain working of universal motor. Give two applications of universal motor.

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Last Answer : A universal motor can run on either A.C. or D.C.

Description : A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be

Last Answer : A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be 474 V

Description : 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

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Description : The speed of a 2-pole, 3-phase stepper motor operated by 1200 pulses/min (A) 100 rpm (B) 200 rpm (C) 400 rpm (D) 800 rpm

Last Answer : The speed of a 2-pole, 3-phase stepper motor operated by 1200 pulses/min 200 rpm

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Last Answer : As the load is increased the speed of D.C. shunt motor will reduce slightly.

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Last Answer : The speed of a D.C. series motor is inversely proportional to the armature current.

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Description : speed control methods of three phase induction motor?

Last Answer : Speed control of three phase induction motor

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Description : An electric motor in which both stator field and rotor rotates with same speed is called?

Last Answer : An electric motor in which both stator field and rotor rotates with same speed is called synchronous motor.

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Description : What human gestures are universal?

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Description : What is a Universal Blood Donor and a Universal Blood Recipient?

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Description : 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

Last Answer : In case the back e.m.f. and the speed of a D.C. motor are doubled, the torque developed by the motor will remain unchanged.