Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 0 Hz 50 Hz 25 Hz 100 Hz 0 Hz 50 Hz 25 Hz 100 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 65.8 Nm. 74 Nm. 27.73 Nm . 38.5 Nm. 65.8 Nm. 74 Nm. 27.73 Nm . 38.5 Nm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the increase in the torque expressed as percentage of initial torque, if current drawn by the dc series motor is increased from 10A to 11A? 11% 10% 41% 21% 11% 10% 41% 21% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC generators has rising V-I characteristics? None of them. Series. Compound. Shunt. None of them. Series. Compound. Shunt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The crawling in the induction motor is caused by harmonics developed in the motor improper design of stator laminations low voltage supply high loads harmonics developed in the motor improper design of stator laminations low voltage supply high loads ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will open fuse or circuit breaker. produce sparking at brushes. draw too much current. develop excessive speed and damage itself. open fuse or circuit breaker. produce sparking at brushes. draw too much current. develop excessive speed and damage itself. ANSWER DOWNLOAD EXAMIANS APP