What will happen if the back e.m.f. of a D.C. motor vanishes suddenly?
Correct answer: C. The armature may burn
- A. The motor will stop
- B. The motor will continue to run
- C. The armature may burn
- D. The motor will run noisy
Explanation
If back e.m.f. disappears while the supply remains connected, the opposing voltage is lost and the armature current can rise to a dangerously high value. This excessive current may overheat and burn the armature.
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