A. hysteresis loss
B. magnetisation of rotor
C. eddy current loss
D. electromagnetic induction
A. brush axis is 45° electrical to field axis
B. brush axis coincides with the field axis
C. brush axis is 90° electrical to field axis
D. both B. and (c)
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. Repulsion motor
B. Reluctance motor
C. Hysteresis motor
D. Universal motor
A. a single turn of heavy wire which is in parallel with running winding
B. a single turn of heavy copper wire which is short-circuited and carries only induced current
C. a multilayer fine gauge copper wire in parallel with running winding
D. none of the above
A. Electric shavers
B. Refrigerators
C. Signalling and timing devices
D. Lifts and hoists
A. improve power factor
B. increase overload capacity
C. reduce fluctuations in torque
D. to improve torque