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# Rotating Magnetic Field - Electrical Machines MCQs

Rotating Magnetic Field MCQs : Here you will find MCQ Questions related to "Rotating Magnetic Field" in Electrical Machines. These Rotating Magnetic Field MCQ Questions Will help you to improve your Electrical Machines knowledge and will prepare you for various Examinations like Competitive Exams, Placements, Interviews and other Entrance Exmaniations.

Question 1

The rotating magnetic filed is the key principle in the operation of?

A. reluctance Motor
B. induction machines
C. machine ratings
D. None of the above

Question 2

The induction motor consists of a?

A. stator
B. rotor
C. Both A and B
D. None of the above

Question 3

A symmetric rotating magnetic field can be produced with as few as two polar wound coils driven at _____________ phasing.

A. 0-degree
B. 30-degree
C. 60-degree
D. 90-degree

Question 4

A rotating magnetic field is the resultant magnetic field produced by a system of coils symmetrically placed and supplied with polyphase currents.

A. TRUE
B. FALSE
C. Can be true and false
D. Can not say

Question 5

The speed at which rotating magnetic field revolves is called?

A. Induction speed
B. Synchronous speed
C. Relative speed
D. Rotating speed

Question 6

If the phase sequence of supply currents are reversed, then the direction of rotation of the resultant MMF wave will ___________

A. Remains unchanged
B. Cannot be determined
C. Be reversed
D. None of the above

Question 7

When a single-phase winding is excited by an alternating current, then which of the following statements are correct?

A. It produces one stationary MMF wave
B. Produced MMF wave pulsates along its magnetic axis
C. It doesnâ€™t produce two counter rotating MMF wave
D. All of the above

Question 8

The three coils are driven with each set _________ in phase from the others

A. 90 degrees
B. 45 degrees
C. 120 degrees
D. 180 degrees

Question 9

Three phase voltages are applied to the three windings of an electrical machine. If any two supply terminals are interchanged, then the rotating MMF wave _____________

A. Direction reverses, amplitude alters
B. Direction reverses, amplitude unaltered
C. Direction remains same, amplitude alters
D. Direction remains same, amplitude unaltered