Electrical Machines
For a given torque, reducing divertor resistance of a DC series motor

  Increase in speed but armature currnet remains the same.
  Decrease in speed but armature current remains the same.
  Increase in speed demanding more armature current.
  Decrease in speed demanding less armature current.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
In DC machines, the interpoles are provided

 to counteract the reactance voltage and the cross-magnetizi
  to make commutation spark less.
 to counteract demagnetizing effect of armature mmf in commutating zone.
  both (B) and (C).

ANSWER DOWNLOAD EXAMIANS APP