Electrical Machines If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 115 V 460 V 200 V 230 V 115 V 460 V 200 V 230 V 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 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° shift forward by more than 90° shift forward by less than 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a 50 Hz three phase induction motor under full load condition is 725 rpm the number of poles of the motor are ______________. 6. 8. 2. 4. 6. 8. 2. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flashing the field of DC generator means neutralising residual magnetism. increasing flux density by adding extra turns of winding. creating residual magnetism by a DC source. making the magnetic losses forces parallel. neutralising residual magnetism. increasing flux density by adding extra turns of winding. creating residual magnetism by a DC source. making the magnetic losses forces parallel. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Breather is provided in a transformer to provide cold air in transformer. absorb moisture from air entering in transformer. filter the transformer oil. absorb moisture of air during breathing. provide cold air in transformer. absorb moisture from air entering in transformer. filter the transformer oil. absorb moisture of air during breathing. 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 2, 3 1, 4 1, 3 2, 4 2, 3 1, 4 1, 3 2, 4 ANSWER DOWNLOAD EXAMIANS APP