Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the field excitation. varying the applied voltage. changing the load. varying the speed. changing the field excitation. varying the applied voltage. changing the load. varying the speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The crawling in the induction motor is caused by improper design of stator laminations low voltage supply harmonics developed in the motor high loads improper design of stator laminations low voltage supply harmonics developed in the motor high loads ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. decreased. remains same. increased. kept constant to certain value. decreased. remains same. increased. kept constant to certain value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along field axis. in none of above positions. in any of above positions. along neutral axis. along field axis. in none of above positions. in any of above positions. along neutral axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V – IaRa. E = V + Ia. E = V + Ra. E = V + IaRa. E = V – IaRa. E = V + Ia. E = V + Ra. E = V + IaRa. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, the field system has to be provided on stator unlike synchronous machines Where in it could be on any member, because it reduces field structure iron losses dc machines are comparatively low rating machines. commutator action is not possible otherwise it gives more uniform air-gap flux distribution it reduces field structure iron losses dc machines are comparatively low rating machines. commutator action is not possible otherwise it gives more uniform air-gap flux distribution ANSWER DOWNLOAD EXAMIANS APP
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