In a 3-phase synchronous motor; ...

In a 3-phase synchronous motor; 

(A) the speed of the stator MMF is always more than that of the rotor MMF (B) the speed of the stator MMF is always less than that of the rotor MMF (C) the speed of the stator MMF is synchronous speed while that of the rotor MMF is zero (D) the rotor and the stator MMF are stationary with respect to each other
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Answer :

In a 3 -phase synchronous motor:  the rotor and the stator MMF are stationary with respect to each other

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