Electrical Machine MCQs for test preparation. Includes multiple-choice questions and answers on electrical machines, providing a comprehensive resource for students and professionals.
In a DC generator, the commutator is used for :
A. convert AC armature current in to DC
B. increase efficiency
C. collecting of current
D. reduce lossesThe induced emf in the armature winding of the DC generator is :
A. AC and DC
B. AC
C. DC
D. NoneCommutator pitches of duplex and simplex lap windings are respectively ____ ?
A. 2 and 1
B. 2 and 2
C. 4 and 2
D. 4 ang 1The hysteresis loop shows the region of:
A. hysteresis loss
B. total iron losses
C. copper loss
D. eddy current lossThin laminations are used in a machine in order to reduce ____ ?
A. Hysteresis losses
B. Eddy current losses
C. Copper losses
D. Both a nd bThe loss of hysteresis will depend on :
A. f³
B. f1.6
C. f
D. f²Eddy current loss will depends on ____ ?
A. Flux density
B. Thickness
C. Frequency
D. All of themThe best control technique for wide-ranging, highly sensitive speed control is ?
A. Armature control
B. Ward-Leonard control
C. Multiple voltage control
D. Armature resistance controlIn Ward-Leonard system, the lower limit of the speed imposed by ____ ?
A. Residual magnetism of the generator
B. Armature resistance
C. Field resistance
D. None of themWhat is the similar circuit for the shunt resistance component that was derived using an induction motor representative without a load ?
A. Copper loss
B. both 1 and 2
C. bwindage and friction loss
D. core loss only