Electrical Machines For an ideal transformer the winding should have no ohmic resistance on either side minimum resistance on primary side and maximum resistance on secondary side maximum resistance on primary side and least resistance on secondary side equal resistance on primary and secondary side no ohmic resistance on either side minimum resistance on primary side and maximum resistance on secondary side maximum resistance on primary side and least resistance on secondary side equal resistance on primary and secondary side ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase transformer the magnitude of leakage reactance is twice that of resistance of both primary and secondary. With secondary short circuited, the input power factor is 1/√2 1/3 2/√5 1/√5 1/√2 1/3 2/√5 1/√5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA 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 speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are the methods to reduce the armature reaction and its effects? All of these pole stacking pole chamfering compensating winding All of these pole stacking pole chamfering compensating winding 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 2, 3 1, 4 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 460 V. 115 V. 230 V. 200 V. 460 V. 115 V. 230 V. 200 V. ANSWER DOWNLOAD EXAMIANS APP
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