Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 16.67 Hz. 60 Hz. 50 Hz. 25 Hz. 16.67 Hz. 60 Hz. 50 Hz. 25 Hz. 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, 4 ,5 1, 4 1, 3, 5 2, 3 , 5 2, 4 ,5 1, 4 1, 3, 5 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of rotor current of 50 Hz induction motor operating at 4% slip? 2HZ 50Hz 2.5Hz 1 Hz 2HZ 50Hz 2.5Hz 1 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Compensating windings are used in DC generators to neutralize the cross magnetizing effect of the armature reaction. None of these mainly to reduce the eddy currents by providing local short circuit. to provide path for the circulation of cooling air. to neutralize the cross magnetizing effect of the armature reaction. None of these mainly to reduce the eddy currents by providing local short circuit. to provide path for the circulation of cooling air. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Equalizer rings are used in which of the followings? None of these lap winding wave winding both 1 and 2 None of these lap winding wave winding both 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor electromotive force of the IM is observed to make 100 complete alterations per minute, calculated slip None of these 0 .001 %. 3 %. 3.33 %. None of these 0 .001 %. 3 %. 3.33 %. ANSWER DOWNLOAD EXAMIANS APP