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% 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% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer operating at constant voltage if the input frequency increases, the core loss increase. decrease. None of these remains constant. increase. decrease. None of these remains constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between stator and the rotor of the 3 - φ induction motor is kept as small as possible. air gap does not matter. depends on the material of stator and the rotor. as wide as possible. as small as possible. air gap does not matter. depends on the material of stator and the rotor. as wide as possible. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Motor 3 point starter is used to all of above. provide protection against Low-Voltage. limit the starting current to a safer value. provide overload protection. all of above. provide protection against Low-Voltage. limit the starting current to a safer value. provide overload protection. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 3 2, 4 1, 4 1, 3 2, 3 2, 4 1, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Armature circuit resistance control. Armature voltage control. Any of above. Field resistance control. Armature circuit resistance control. Armature voltage control. Any of above. Field resistance control. ANSWER DOWNLOAD EXAMIANS APP
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