Electrical Machines Semi closed slots or totally closed slots are used in induction motors, essentially to increase pull out torque improve starting torque decrease starting torque reduce magnetising current and improve power factor increase pull out torque improve starting torque decrease starting torque reduce magnetising current and improve power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Counter emf of a DC motor aids applied voltage. exceeds supply voltage regulates its armature voltage. helps in energy conversion. aids applied voltage. exceeds supply voltage regulates its armature voltage. helps in energy conversion. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a practical synchronous motor the pull out torque will occur when the torque angle is nearly equal to 45°. 30°. 0°. 75°. 45°. 30°. 0°. 75°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous speed of an induction motor will be increased by increasing of frequency. speed can not be increased. decreasing of frequency. increasing number of poles. increasing of frequency. speed can not be increased. decreasing of frequency. increasing number of poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be doubled. It will be halved. It will becomes four times. It will remain the same. It will be doubled. It will be halved. It will becomes four times. It will remain the same. ANSWER DOWNLOAD EXAMIANS APP
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