M

Mr. Dubey • 52.30K Points
Coach 

Q. Plugging is applied in a motor, if we don’t make the switch OFF what will happen?

(A) motor will come to rest as a result of plugging
(B) motor will come to rest and will start rotating in another direction
(C) motor will burn
(D) nothing will happen
Correct : Option (B)

Explanation: 
 if the switch is kept on near to zero speed, motor will have braking torque acting in opposite direction greater than the electromechanical torque. thus, motor will come to rest and for the next instant motor will start rotating in opposite direction.

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