Electrical Machines With the increase in speed of a DC motor back emf falls and line current increases. both back emf as well as line current increase. back emf increases but line current falls. both back emf as well as line current fall. back emf falls and line current increases. both back emf as well as line current increase. back emf increases but line current falls. both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following induction motor has the highest starting torque? Squirrel cage induction motor. Same in both induction motors. None of these Slip ring induction motor. Squirrel cage induction motor. Same in both induction motors. None of these Slip ring induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, alternator has generated emf per phase of 230 V with 10% 3rd harmonic and 6% 5th harmonic content. Calculate rms line voltage for star connection. 399 V. 100 V. 50 V. 230.2 V. 399 V. 100 V. 50 V. 230.2 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is done in speed control of DC motor by field flux control? Inserting resistance to armature circuit and field circuit. Any of above. Inserting an additional resistance in the armature circuit. Inserting an additional resistance in the field circuit. Inserting resistance to armature circuit and field circuit. Any of above. Inserting an additional resistance in the armature circuit. Inserting an additional resistance in the field circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip exists in synchronous motor. in both machines. none of above. induction motor. synchronous motor. in both machines. none of above. induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A smaller air gap in a polyphase induction motor helps to reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. reduce the chance of cogging. increase the starting torque. reduce the chance of crawling. reduce the magnetizing current. ANSWER DOWNLOAD EXAMIANS APP