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 6% and -4% 3.2% and -1.6% None of these 4.8% and -3.2% 6% and -4% 3.2% and -1.6% None of these 4.8% and -3.2% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Due to magnetic saturation, the flux per pole in a DC machine without brush shift decreases in both generators and the motors with load. decreases in generators and increases in motor with load. increases in both the generators and the motors with load. increases in generators but decreases in motor with load. decreases in both generators and the motors with load. decreases in generators and increases in motor with load. increases in both the generators and the motors with load. increases in generators but decreases in motor with load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause heating of rotor. double frequency currents in the rotor. vibrations. All of these heating of rotor. double frequency currents in the rotor. vibrations. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V. can not be determined. 266.20 N-m. 234.76 N-m. 133.22 N-m can not be determined. 266.20 N-m. 234.76 N-m. 133.22 N-m ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Variation in speed by ward-Leonard control of DC motors occurs due to variation in Field excitaion. Armature current. Supply voltage. Armature voltage. Field excitaion. Armature current. Supply voltage. Armature voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce hysteresis loss only. increase the permeability. reduce eddy current loss only. reduce both eddy current and hysteresis loss. reduce hysteresis loss only. increase the permeability. reduce eddy current loss only. reduce both eddy current and hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP