In a 3-phase synchronous motor (A) the speed of stator MMF is always more than that of rotor MMF. (B) the speed of stator MMF is always less than that of rotor MMF. (C) the speed of stator MMF is synchronous speed while that of rotor MMF is zero. (D) rotor and stator MMF are stationary with respect to each other.

In a 3-phase synchronous motor
 (A) the speed of stator MMF is always more than that of rotor MMF.
 (B) the speed of stator MMF is always less than that of rotor MMF.
 (C) the speed of stator MMF is synchronous speed while that of rotor MMF is zero.
 (D) rotor and stator MMF are stationary with respect to each other.
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1 Answer

Answer :

Ans: D
Because, Motor is magnetically locked into position with stator, the rotor poles are
engaged with stator poles and both run synchronously in same direction Therefore,
rotor & stator mmf are stationary w.r.t each other.
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