Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 50 Hz. 16.67 Hz. 25 Hz. 60 Hz. 50 Hz. 16.67 Hz. 25 Hz. 60 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output power of a dc motor is given by EIa. EbIa. EbIa2. none of these. EIa. EbIa. EbIa2. none of these. ANSWER DOWNLOAD EXAMIANS APP
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. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. deteriorate with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a star - delta starting of an IM line voltage is 57.7 % of stator voltage. reduced voltage is applied to the stator. resistance is inserted in the rotor. applied voltage per stator phase is 57.7 % of a line volt line voltage is 57.7 % of stator voltage. reduced voltage is applied to the stator. resistance is inserted in the rotor. applied voltage per stator phase is 57.7 % of a line volt ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is prefered for which of the following rating? low current and low voltage high current and high voltage low current and high voltage high current and low voltage low current and low voltage high current and high voltage low current and high voltage high current and low voltage ANSWER DOWNLOAD EXAMIANS APP
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