At a very low speed, increase in field resistance will _________(a) decrease the speed of motor(b) increase the speed of motor(c) not have signicant effect on speed(d) no effectThe question was asked in semester exam.My question is based upon Speed Control of DC Motors topic in portion DC Motors of Electrical Machines

At a very low speed, increase in field resistance will _________(a) de

1.	At a very low speed, increase in field resistance will _________(a) decrease the speed of motor(b) increase the speed of motor(c) not have signicant effect on speed(d) no effectThe question was asked in semester exam.My question is based upon Speed Control of DC Motors topic in portion DC Motors of Electrical Machines
Answer» The correct option is (a) decrease the speed of motor To explain: At low speed increase in ARMATURE CURRENT caused by decrease in emf, will not be enough to compensate for decrease in flux in induced TORQUE EQUATION.

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