In order to run an induction motor at synchronous speed __________ – McqOptions

MCQOPTIONS

1.	In order to run an induction motor at synchronous speed __________
A.	load must be reduced
B.	friction at bearing must be reduced
C.	e.m.f must be injected in the rotor in a phase with rotor e.m.f
D.	e.m.f. must be injected in the rotor in a phase opposite to the rotor e.m.f.
Answer» D. e.m.f. must be injected in the rotor in a phase opposite to the rotor e.m.f.

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