DC Generators Carbon brushes are used in a dc machine because _______ Carbon is cheap Contact resistance is decreased Carbon lubricates and polishes the commutator None of the listed here Carbon is cheap Contact resistance is decreased Carbon lubricates and polishes the commutator None of the listed here ANSWER DOWNLOAD EXAMIANS APP
DC Generators The number of parallel paths in a simplex lap winding is equal to None of the listed here Number of pairs of poles 2 Number of poles None of the listed here Number of pairs of poles 2 Number of poles ANSWER DOWNLOAD EXAMIANS APP
DC Generators Small dc machines generally have _____ poles. 2 4 6 8 2 4 6 8 ANSWER DOWNLOAD EXAMIANS APP
DC Generators If residual magnetism is present in a D.C. generator, the induced e.m.f. at zero speed will be Small The same as rated voltage High Zero Small The same as rated voltage High Zero ANSWER DOWNLOAD EXAMIANS APP
DC Generators When two D.C. series generators are running in parallel, an equalizer bar is used To increase the series flux To increase the speed and hence generated e.m.f. So that two similar machines will pass approximately equal currents to the load To reduce the combined effect of armature reaction of both machines To increase the series flux To increase the speed and hence generated e.m.f. So that two similar machines will pass approximately equal currents to the load To reduce the combined effect of armature reaction of both machines ANSWER DOWNLOAD EXAMIANS APP
DC Generators The armature of dc machine is laminated in order to reduce Copper loss Hysteresis loss Frictional loss Eddy current loss Copper loss Hysteresis loss Frictional loss Eddy current loss ANSWER DOWNLOAD EXAMIANS APP
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