Electrical Machines Commutator in DC generator is used for collecting of current increase efficiency convert AC armature current in to DC reduce losses collecting of current increase efficiency convert AC armature current in to DC reduce losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a 3-phase induction motor operating in its stable region remains constant. increases with increase in the load torque. decreases with decrease in the load torque. decreases with increase in the load torque. remains constant. increases with increase in the load torque. decreases with decrease in the load torque. decreases with increase in the load torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical load on it because otherwise it will develop excessive speed and damage itself. draw too much current. produce sparking at brushes. open fuse or circuit breaker. develop excessive speed and damage itself. draw too much current. produce sparking at brushes. open fuse or circuit breaker. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum efficiency will occur, when copper loss is_______to iron loss? less than greater than any of the above equal to less than greater than any of the above equal to ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to reduce eddy current losses by providing local short circuits. neutralize voltage induced in coil due to fluctuation of l None of these compensate for the decrease in speed due to increase of load. reduce eddy current losses by providing local short circuits. neutralize voltage induced in coil due to fluctuation of l None of these compensate for the decrease in speed due to increase of load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature MMF waveform of a DC machine is rectangular. triangular. pulsating. sinusoidal. rectangular. triangular. pulsating. sinusoidal. ANSWER DOWNLOAD EXAMIANS APP
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