Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 3.05+j5.08 ohms 8+j13 ohms 53+j85 ohms 3.5+j5.8 ohms 3.05+j5.08 ohms 8+j13 ohms 53+j85 ohms 3.5+j5.8 ohms ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A part an alternator winding consist of eight coils in series, each having an emf of 20 V rms induced in it. Coils are placed in successive slots and between each slot and the next, there is an electrical phase displacement of 30°. Find the emf of eight coils in series 56.91 V. 86.91 V. 76.91 V. 66.91 V. 56.91 V. 86.91 V. 76.91 V. 66.91 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Addition of 0.3 % to 4.5 % silicon to iron increases the electrical resistivity of iron. reduces the saturation magnetization. None of these increases the hysteresis loss. increases the electrical resistivity of iron. reduces the saturation magnetization. None of these increases the hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In circle diagram for induction motor, diameter of circle represents which of the following ? Rotor current. Line voltage. Running torque. Slip. Rotor current. Line voltage. Running torque. Slip. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Lamination of transformer core is made of wrought iron. silicon steel. cast iron. cast steel. wrought iron. silicon steel. cast iron. cast steel. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 ANSWER DOWNLOAD EXAMIANS APP