Electrical Machines The low voltage winding of a 400/230 V single phase 50 Hz transformer is to be connected to keep the magnetization current at the same level in both the cases the voltage at 25 Hz should be 230 V 460 V 65 V 115 V 230 V 460 V 65 V 115 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a dc motor the ratio Eb / E is indicative of efficiency. ratio of starting to running torque. ratio of starting to running current. ratio of input to output voltage. efficiency. ratio of starting to running torque. ratio of starting to running current. ratio of input to output voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is 0 Hz 1 Hz 5 Hz 50 Hz 0 Hz 1 Hz 5 Hz 50 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In travelling cranes for swing action which motor is preferred? DC series motor. Capacitor type induction motors. Reluctance motor. AC slip ring IM. DC series motor. Capacitor type induction motors. Reluctance motor. AC slip ring IM. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of these types of motor is used in elevators? DC shunt motor. DC compound motor. DC series motor. None of these. DC shunt motor. DC compound motor. DC series motor. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing divertor resistance of a DC series motor Decrease in speed demanding less armature current. Increase in speed demanding more armature current. Decrease in speed but armature current remains the same. Increase in speed but armature currnet remains the same. Decrease in speed demanding less armature current. Increase in speed demanding more armature current. Decrease in speed but armature current remains the same. Increase in speed but armature currnet remains the same. ANSWER DOWNLOAD EXAMIANS APP