A. a stronger commutating field is needed at low speed than at high speed
B. a weaker commutating field is needed at low speed than at high speed
C. same commutating field is needed at low speed than at high speed
D. none of the above is correct
A. self-induced e.m.f.
B. mutually induced e.m.f.
C. back e.m.f
D. none of the above
A. drum type controller is used
B. three point starter is used
C. four point starter is used
D. all above can be used
A. this will make armature to take heavy current, possibly burning it
B. this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
C. nothing will happen to motor
D. motor will come to stop
A. series motor
B. shunt motor
C. compound motor
D. any of the above
A. series motor
B. shunt motor
C. compound motor
D. any of the above
A. Series motor
B. Shunt motor
C. Cumulatively compounded motor
D. Differentially compounded motor
A. the field
B. the armature
C. the brushes
D. the commutator
A. reducing the field current
B. decreasing the armature current
C. increasing the armature current
D. increasing the excitation current
E. none of the above methods