Electrical Machines A 4 pole dc generator is running at 1500 rpm the frequency of current in the armature winding is 200Hz. 100Hz. 150Hz. 50Hz. 200Hz. 100Hz. 150Hz. 50Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed regulation of a DC motor is given as (NnL − NfL)/NfL. NnL − NfL. (NfL − NnL)/NnL. NnL/NfL. (NnL − NfL)/NfL. NnL − NfL. (NfL − NnL)/NnL. NnL/NfL. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To avoid formation of grooves in the commutator None of these the brushes of opposite polarity should track each other. the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. None of these the brushes of opposite polarity should track each other. the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction in dc motor results short circuit. increase in speed. open circuit. decrease in speed. short circuit. increase in speed. open circuit. decrease in speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flux density under trailing pole tips in case of generator will decrease None of these either increase or decrease increase decrease None of these either increase or decrease increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC motors are stopped by opening line switches and not by forcing the handle of the motor starter back to OFF position. This is due to occurance of None of these. Both of above. Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. None of these. Both of above. Heavy sparking at the first stud of starting resistance steps. Heavy sparking at brushes. ANSWER DOWNLOAD EXAMIANS APP
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