A. 95% to 99%
B. 80% to 90%
C. 50% to 75%
D. 5% to 35%
A. universal motor
B. D.C. shunt motor
C. single-phase capacitor run motor
D. 3-phase synchronous motor
A. thick wire placed at the bottom of the slots
B. thick wire placed at the top of the slots
C. thin wire placed at the top of the slots
D. thin wire placed at the bottom of the slots
A. smaller brush width
B. less number of field turns
C. more number of armature turns
D. less air gap
E. all of the above
A. varying field flux with tapped field windings
B. connecting rheostat in series
C. applying variable voltage by means of silicon controlled rectifier
D. applying variable voltage by means of variable auto-transformer
E. all of the above methods
A. slip rings
B. commutator
C. both A. and (b)
D. none of the above
A. improve power factor
B. increase overload capacity
C. reduce fluctuations in torque
D. to improve torque