M

Mr. Dubey • 52.30K Points
Coach 

Q. Sparking is discouraged in a DC motor.

(A) true
(B) false
(C) ---
(D) ---
Correct : Option (B)

Explanation: 
 sparking at brushes and commutator segments lead to damage of commutators, which is the main distinguishable component in a dc machine. so, it is advisable to fasten the commutation speed and avoid sparking.

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