In a synchronous generator delivering lagging power factor load

In a synchronous generator delivering lagging power factor load 

(1) the excitation emf leads terminal voltage by the power angle (2) the excitation emf lags terminal voltage by the power angle (3) excitation emf leads the terminal voltage by the power factor angle (4) excitation emf lags the terminal voltage by the power factor angle
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Answer :

In a synchronous generator delivering lagging power factor load the excitation emf leads terminal voltage by the power angle

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Related questions

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The power factor angle and torque angle of a salient pole synchronous generator drawing a current of 1.0 pu

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