How energy conversion takes place in dc machines (motor or generator)
You should grab a textbook for an explanation. Wikipedia probably has something on this as well. It's too much to explain how it works in one post.
ok i better ask specific questions so that it wud be easier to answer.first of all in generators how and wat force is produced,that resists the motion of armature being moved by a prime mover.
A current is produced in the generator which would oppose the magnetic field (usually of permanent magnets). This is Lenz's Law in action. And I second taking a look at the Wikipedia articles on generators and motors, which will give you a high-level introduction to this topic. After that, perhaps an introductory electromagnetics textbook? You're asking a lot with this question.
energy coonversion is taking place in dc machines by the action of lenz law.current passes thru the coil which felts under magnetic field and turns to induction principle.ie: curren carrying conductor in a magnetic field effects a force which inturns into a torque.
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