Electrical Machines Which of the following is/are the advantages of carbon brush over the copper brush? 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 They are not hard as copper brush All of these In case of any sparking they will be less damaged than copper brushes 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 10% increased by 10% reduced by 20% increased by 20% reduced by 10% increased by 10% reduced by 20% increased by 20% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For successful parallel operation of two single phase transformers, the most essential condition is that their KVA ratings are equal polarities are properly connected turn- ratios are exactly equal percentage impedances are equal KVA ratings are equal polarities are properly connected turn- ratios are exactly equal percentage impedances are equal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer which of the following losses are zero? Iron loss All of these Rotational loss Copper loss Iron loss All of these Rotational loss Copper loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Counter emf of a DC motor helps in energy conversion. exceeds supply voltage aids applied voltage. regulates its armature voltage. helps in energy conversion. exceeds supply voltage aids applied voltage. regulates its armature voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power input to a 3 - φ induction motor is 60 kW and stator loss is 1 kW the rotor cu loss per phase is slip X 69 / 3. slip X 50 / 3. slip X 59 / 3. 1. slip X 69 / 3. slip X 50 / 3. slip X 59 / 3. 1. ANSWER DOWNLOAD EXAMIANS APP