Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value changes to 0.5 times the original value changes to three times the original value remain the same as the original changes to 1.5 times the original value changes to 0.5 times the original value changes to three times the original value remain the same as the original ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A small air gap in poly phase induction motor helps to reduce chance of crawling. reduce chance of cogging. increase starting torque. reduce magnetizing current. reduce chance of crawling. reduce chance of cogging. increase starting torque. reduce magnetizing current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutator in DC generator is used for increase efficiency collecting of current convert AC armature current in to DC reduce losses increase efficiency collecting of current convert AC armature current in to DC reduce losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power factor of an induction motor operating at no load will have a value around 0.9 lag unity 0.2 lag 0.2 lead 0.9 lag unity 0.2 lag 0.2 lead ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The heat generated in the transformer is dissipated mainly by convection. All of these conduction. radiation. convection. All of these conduction. radiation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC generator runs at 750 rpm and generate an emf of 240 V. The armature is wave wound and has 792 conductors. If the total flux from each pole is 0.0145 Wb. What is the leakage co-efficient? 1.2. 1.5. 1.4. 1.8. 1.2. 1.5. 1.4. 1.8. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS