in an alternater at what power factor the effect armature reaction is de-magnetizing....

A. at 0.8 p.f B. at 0.5 p.f c. at zero p.f D. at unity p.f

Your Answer

At zero bcoz At unity power factor, the angle between armature current I and induced emf E, is zero. That means, armature current and induced emf are in same phase. But we know theoretically that emf induced in the armature is due to changing main field flux, linked with the armature conductor.

1
online electrical engineering test
Practice Mock Test
online electrical engineering test