Electrical Machines When operating, two or more transformers in parallel, % impedance of these transformers should be such that actual impedance of all transformers would be same. inversely proportional to MVA rating of transformers. same. proportionate to MVA rating of transformers. such that actual impedance of all transformers would be same. inversely proportional to MVA rating of transformers. same. proportionate to MVA rating of transformers. ANSWER DOWNLOAD EXAMIANS APP
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% increased by 10% reduced by 10% increased by 20% reduced by 20% increased by 10% reduced by 10% increased by 20% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous generator a synchronous dead load (lamp, furnaces etc) has no ____________ hence it has no natural frequency of oscillation. mechanical rotatory system. damping torque. synchronizing power co efficient. restoring torque. mechanical rotatory system. damping torque. synchronizing power co efficient. restoring torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main purpose of providing tertiary winding in a three phase transformer is to suppress harmonic and unbalance in voltage. to carry extra load. to interconnect three voltage systems. None of these to suppress harmonic and unbalance in voltage. to carry extra load. to interconnect three voltage systems. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 5% 4% 2% 25% 5% 4% 2% 25% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direction of rotation of DC motor is reversed by Adding resistance to field circuit. Interchanging armature and field connection. Reversing armature connection or field connection. Reversing supply connection. Adding resistance to field circuit. Interchanging armature and field connection. Reversing armature connection or field connection. Reversing supply connection. ANSWER DOWNLOAD EXAMIANS APP
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