Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 100 Hz. Zero Hz. 50 Hz. 25 Hz. 100 Hz. Zero Hz. 50 Hz. 25 Hz. 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 in the same as that while running. power factor at starting is high as compared to that while running. none of them. power factor at starting is low as compared to that while running. power factor at starting in the same as that while running. power factor at starting is high as compared to that while running. none of them. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Reduce. Remain unaltered. Increase. Oscillate around the normal speed. Reduce. Remain unaltered. Increase. Oscillate around the normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - φ induction motor running at full load which of these parameters is stationary with respect to the stator mmf wave? Stator winding. Rotor mmf wave. Rotor winding. Both rotor and stator winding. Stator winding. Rotor mmf wave. Rotor winding. Both rotor and stator winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The principle of dynamically induced emf is utilized in choke. generator. thermocouple. transformer. choke. generator. thermocouple. transformer. ANSWER DOWNLOAD EXAMIANS APP