DC Motors The back emf in a dc motor ______ Aids the armature current Opposes the applied voltage Aids the applied voltage None of the listed here Aids the armature current Opposes the applied voltage Aids the applied voltage None of the listed here ANSWER DOWNLOAD EXAMIANS APP
DC Motors If conditions for maximum power for a dc motor are established, the efficiency of the motor will be Less than 50% 100 % 60 to 70 % 80 to 90 % Less than 50% 100 % 60 to 70 % 80 to 90 % ANSWER DOWNLOAD EXAMIANS APP
DC Motors When the speed of dc motor increases, its armature current Remains same Increases None of the listed here Decreases Remains same Increases None of the listed here Decreases ANSWER DOWNLOAD EXAMIANS APP
DC Motors Excessive sparking at brushes may be caused due to Loose coupling Worn bearings Misaligment of machine Dirt on the commutator Loose coupling Worn bearings Misaligment of machine Dirt on the commutator ANSWER DOWNLOAD EXAMIANS APP
DC Motors In dc machines fractional pitch winding is used To reduce the sparking To reduce the generated emf To increase the generated emf To improve cooling To reduce the sparking To reduce the generated emf To increase the generated emf To improve cooling ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which D.C. motor is generally preferred for cranes and hoists? Differentially compounded motor Series motor Cumulatively compounded motor Shunt motor Differentially compounded motor Series motor Cumulatively compounded motor Shunt motor ANSWER DOWNLOAD EXAMIANS APP
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