Electrical Machines Open circuit in a transformer is prefered with rated transformer voltage direct current high frequency supply rated transformer current rated transformer voltage direct current high frequency supply rated transformer current ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Copper brushes in DC machine are used None of these in both of above cases. where low voltage and high currents are involved. where high voltage and low current. None of these in both of above cases. where low voltage and high currents are involved. where high voltage and low current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case the conditions for maximum power for DC motor are established, the efficiency of the motor will be Less than 50 % Any where between 75 % and 90 %. Around 90 % Around 100 %. Less than 50 % Any where between 75 % and 90 %. Around 90 % Around 100 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In alternator, the rotary part is armature. core. none of these. magnetic field poles. armature. core. none of these. magnetic field poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has resistance and reactance in per unit as 0.01 and 0.04 respectively. Its voltage regulation for 0.8 power factor lagging and leading will be None of these 3.2% and -1.6% 4.8% and -3.2% 6% and -4% None of these 3.2% and -1.6% 4.8% and -3.2% 6% and -4% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.5 p.u 0.75 p.u 0.125 p.u 0.25 p.u 0.5 p.u 0.75 p.u 0.125 p.u 0.25 p.u ANSWER DOWNLOAD EXAMIANS APP