reversing the supply connections
interchanging the armature and field connections
adding a resistance in the field circuit
reversing the armature connections or the field connections
zero
3000 r.p.m.
3600 r.p.m.
infinity
motor will run at a very high speed
motor will run at a very low speed
motor will burn
motor will not run at all
armature current is reduced
flux is reduced
line current is reduced
none of these
it will continue to run at the rated speed
its speed will become very high
the motor will stop
its speed will reduce