Electrical Machines An alternator is feeding an infinite busbar. Its prime mover is suddenly shutdown. The alternator will start working as induction motor. continue to work as alternator but the direction of rotation will reverse. come to stand still. continue to work as synchronous motor with same direction of rotation. start working as induction motor. continue to work as alternator but the direction of rotation will reverse. come to stand still. continue to work as synchronous motor with same direction of rotation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the mechanical power developed by a DC series motor is maximum? None of above. Back emf is equal to zero. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. None of above. Back emf is equal to zero. Back emf is equal to applied voltage. Back emf is equal to half the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. E = V + Ra. E = V + IaRa. E = V + Ia. E = V – IaRa. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following are variable losses? shunt field copper loss armature copper loss eddy current loss hysteresis loss shunt field copper loss armature copper loss eddy current loss hysteresis loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 1, 4 2, 3 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous motor is supplying a load at unity power factor. If the load on the motor is increased keeping its excitation and terminal voltage constant, the power factor will remain the same None of these will become lagging will become leading will remain the same None of these will become lagging will become leading ANSWER DOWNLOAD EXAMIANS APP
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