Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 1000 rpm 975 rpm 940 rpm 950 rpm 1000 rpm 975 rpm 940 rpm 950 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited DC generator, running at rated speed, has 6 volts across its armature terminals with no field current. When field winding is excited with one ampere, the voltage builds up to 250 V at no load. In case field current is reduced to zero, with the speed remaining unaltered, the armature terminal voltage would be 6 V more than 6 V less than 6 V zero 6 V more than 6 V less than 6 V zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field of a dc shunt motor gets opened while the motor is running, then the armature current will drop armature will oscillate about original speed as the mean speed motor will become slow. motor will attain dangerously high speed armature current will drop armature will oscillate about original speed as the mean speed motor will become slow. motor will attain dangerously high speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor when the length of the air gap is increased, the magnetizing current of the motor increases while the short circuit current __________________. decreased. increased. remains unchanged. kept constant to certain value. decreased. increased. remains unchanged. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the temperature of armature resistance is increased, the speed of a series motor would increase. not change. decrease. None of above. increase. not change. decrease. None of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following components of a DC generator plays vital role for providing direct electric current of a DC generator? Equalizer rings. Commutator. Eye bolt. Dummy coils. Equalizer rings. Commutator. Eye bolt. Dummy coils. ANSWER DOWNLOAD EXAMIANS APP
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