The supply both to field and armature circuits are disconnected simultaneously in a separately excited dc...

The supply both to field and armature circuits are disconnected simultaneously in a separately excited dc motor and it comes to a standstill in 5 sec. If the armature circuit of this motor is disconnected from supply with field circuit remaining energized, the motor would come to rest in (1) 5 sec (2) 7 sec (3) 4 sec (4) A very long time  
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1 Answer

Answer :

5 sec only.standstill time doesn't depend upon field excitation
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