Electrical Machines The breakdown torque of a synchronous motor varies as V² 1/V applied voltage V 1/V² V² 1/V applied voltage V 1/V² 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 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has the highest power factor at full load? Capacitor run Shaded pole Capacitor start Resistance split phase Capacitor run Shaded pole Capacitor start Resistance split phase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ induction motor power factor at starting is low as compared to that while running. power factor at starting is high as compared to that while running. power factor at starting in the same as that while running. none of them. power factor at starting is low as compared to that while running. power factor at starting is high as compared to that while running. power factor at starting in the same as that while running. none of them. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 3. 4. 7. 12. 3. 4. 7. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starting current of a 3 - Φ induction motor is 5 times the rated current, while rated slip is 4 %, then ratio of starting torque to full load torque is 1. 0.6. 0.8. 0.4. 1. 0.6. 0.8. 0.4. ANSWER DOWNLOAD EXAMIANS APP