A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction

A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is 

(A) magnetizing (B) demagnetizing (C) cross-magnetizing (D) ineffective
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Answer :

A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is demagnetizing 

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The coupling angle or load angle of synchronous motor is defined as the angle between the?

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If the synchronous motor, properly synchronised to the supply is running on no load and is having negligible loss then?

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A hydraulic turbine having rated speed of 250 rpm is connected to a synchronous generator. In order to

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If the excitation is increased to one of two alternators operating in parallel, the _____________. A. power factor will change in the lagging direction B. power factor will change in the leading direction C. kilowatt load will be greatly increased D. ampere load will be greatly decreased

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