A 3~phase synchronous motor, connected to infinite bus, is operating at no load at normal excitation. ...

A 3~phase synchronous motor, connected to infinite bus, is operating at no load at normal excitation. The field excitation of the motor is first decreased to zero and then increased in the reverse direction. The armature current of the synchronous motor will: 

(1) Remain constant. (2) First decrease and then increase, (3) Increases continuously (4) First increase and then decreased
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A 3~phase synchronous motor, connected to infinite bus, is operating at no load at normal excitation. The field excitation of the motor is first decreased to zero and then increased in the reverse direction. The armature current of the synchronous motor will: Increases continuously.

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