Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? They are not hard as copper brush All of these In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature They are not hard as copper brush All of these In case of any sparking they will be less damaged than copper brushes They are self lubricating in nature ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If input of a transformer is square wave the output will be triangular wave. square wave. sine wave. pulsed wave. triangular wave. square wave. sine wave. pulsed wave. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 1600 Volt. 1500 Volt. 0 Volt. 2000 Volt. 1600 Volt. 1500 Volt. 0 Volt. 2000 Volt. 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 1, 4 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 2, 3 ANSWER DOWNLOAD EXAMIANS APP
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. same. proportionate to MVA rating of transformers. inversely proportional to MVA rating of transformers. such that actual impedance of all transformers would be same. same. proportionate to MVA rating of transformers. inversely proportional to MVA rating of transformers. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field of a dc shunt motor gets opened while the motor is running, then the motor will become slow. armature will oscillate about original speed as the mean speed armature current will drop motor will attain dangerously high speed motor will become slow. armature will oscillate about original speed as the mean speed armature current will drop motor will attain dangerously high speed ANSWER DOWNLOAD EXAMIANS APP
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