Electrical Machines With the increase in speed of DC motor Both back emf as well as line current increase. Both back emf as well as line current fall. Back emf falls and line current increase. Back emf increase but line current falls. Both back emf as well as line current increase. Both back emf as well as line current fall. Back emf falls and line current increase. Back emf increase but line current falls. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 400 V, 50 Hz, 30 Hp, three phase IM is drawing 50 A current at 0.8 p.f lagging. The stator and rotor copper losses are 1.5 KW and 900 W respectively. The friction and windage losses are 1050 W and core losses are 1200 W. The air gap power of the motor will be 23.06 kW. 25 kW. 24.11 kW. 26.21 kW. 23.06 kW. 25 kW. 24.11 kW. 26.21 kW. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Tap changer is generally provided in voltage transformer. earthing transformer. current transformer. power transformer. voltage transformer. earthing transformer. current transformer. power transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When maximum starting torque is obtained, rotor power is ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 82.5% 78.5% 67.5% 72.5% 82.5% 78.5% 67.5% 72.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following induction motor has the highest starting torque? 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 Same in both induction motors. ANSWER DOWNLOAD EXAMIANS APP
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