Electrical Machines The condition for maximum running torque is zero R = S.X 0.5 lagging unity 0.707 lagging zero R = S.X 0.5 lagging unity 0.707 lagging ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will continue to work as synchronous motor with same direction of rotation. continue to work as alternator but the direction of rotation will reverse. come to stand still. start working as induction motor. continue to work as synchronous motor with same direction of rotation. continue to work as alternator but the direction of rotation will reverse. come to stand still. start working as induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two of supply terminals to a 3 - Φ induction motor get interchanged during re-connection after normal maintenance. When switched on the supply, the motor will rotate in direction opposite to that before maintenance. rotate in the same direction as before maintenance. not start at all. get heated and damaged. rotate in direction opposite to that before maintenance. rotate in the same direction as before maintenance. not start at all. get heated and damaged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4 2, 3 ,5 2, 3, 4, 5 1, 2, 3 2, 3, 4 2, 3 ,5 2, 3, 4, 5 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An IM cannot run at synchronous speed because none of above. air friction will prevent it. rotor torque will not be produced. induction motor will become synchronous motor. none of above. air friction will prevent it. rotor torque will not be produced. induction motor will become synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The polarity of a DC generator can be reversed by reversing field electric current as well as direction of rotation. reversing the field current. increasing field current. any of above. reversing field electric current as well as direction of rotation. reversing the field current. increasing field current. any of above. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS