Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate with fall of terminal voltage. improve with rise in terminal voltage. improve with fall of terminal voltage. deteriorate with rise in terminal voltage. deteriorate with fall of terminal voltage. improve with rise in terminal voltage. improve with fall of terminal voltage. deteriorate with rise in terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer maximum flux density is not constant, the eddy current loss varies as V² f f² V V² f f² V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is 0 Hz 1 Hz 50 Hz 5 Hz 0 Hz 1 Hz 50 Hz 5 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines DC machine windings are None of these short pitched either of these full pitched None of these short pitched either of these full pitched ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under commutation results in sparking the trailing edge of the brush. sparking at the middle of the brush. sparking at the leading edge of the brush. no sparking. sparking the trailing edge of the brush. sparking at the middle of the brush. sparking at the leading edge of the brush. no sparking. ANSWER DOWNLOAD EXAMIANS APP