In a four-pole D.C. machine____________?
Correct answer: B. alternate poles are north and south
- A. all the four poles are north poles
- B. alternate poles are north and south
- C. all the four poles are south poles
- D. two north poles follow two south poles
Explanation
Adjacent poles in a DC machine must have opposite polarities so that the armature conductors experience alternating magnetic fields. Therefore, the poles occur alternately as north and south.
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