Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to applied voltage. None of above. Back emf is equal to zero. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. None of above. Back emf is equal to zero. Back emf is equal to half the applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC shunt generator having a wave winding supplies 50 lamps, each of 60 W at 120 V. The armature and field resistance are 0.2 Ω and 60 Ω respectively. The current in each armature conductor is 13.5 A. 27 A. 23 A. 11.5 A. 13.5 A. 27 A. 23 A. 11.5 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the supply terminal of a DC shunt motor are interchanged The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The motor will stop. The direction of rotation will reverse. The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The motor will stop. The direction of rotation will reverse. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a Dc generator the magnetic neutral axis coincide with geometrical neutral axis, when the generator runs on full load. the generator runs on overload. the generator runs on designed speed. there is no load on the generator. the generator runs on full load. the generator runs on overload. the generator runs on designed speed. there is no load on the generator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 10 Ω. 4 Ω. 2 Ω. 8 Ω. 10 Ω. 4 Ω. 2 Ω. 8 Ω. ANSWER DOWNLOAD EXAMIANS APP