Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be reduced by 20% reduced by 10% increased by 10% increased by 20% reduced by 20% reduced by 10% increased by 10% increased by 20% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 ,V 15 , kW 100 rpm shunt motor with armature resistance of 0.25 , W has a rated line current of 68 A and a rated field current of 2.2 A. The change in field flux required to obtain a speed of 1600 rpm while drawing a line current of 52.8 A and a field current of 1.8 A is 18.18% increase 36.36% increase 36.36% decrease 36.36% increase 18.18% increase 36.36% increase 36.36% decrease 36.36% increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines CRGO steel is used in the core of transformer to reduce eddy current loss. both eddy current and hysteresis loss. hysteresis loss. ohmic loss. eddy current loss. both eddy current and hysteresis loss. hysteresis loss. ohmic loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called resonance. crawling. cogging. harmonics. resonance. crawling. cogging. harmonics. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator in case the brushes are moved so as to bring them in magnetic neutral axis, then, there will be cross-magnetization as well as demagnetization. demagnetisation. none of above. cross-magnetisation. cross-magnetization as well as demagnetization. demagnetisation. none of above. cross-magnetisation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following induction motor has the highest starting torque? Same in both induction motors. Slip ring induction motor. Squirrel cage induction motor. None of these Same in both induction motors. Slip ring induction motor. Squirrel cage induction motor. None of these ANSWER DOWNLOAD EXAMIANS APP
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