In which of the following device the generated emf and armature current are in the opposite directions?
Correct answer: B. dc motor
- A. dc generator
- B. dc motor
- C. transformer
- D. all of the above
Explanation
In a DC motor, the generated back emf opposes the applied voltage and armature current, which is why it is called back emf. In a generator, the generated emf drives the armature current rather than opposing it.
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