Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 50 Hz 100 Hz 25 Hz 0 Hz 50 Hz 100 Hz 25 Hz 0 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction in a DC machine is in the same direction as the main poles. makes an angle with the main pole axis which is load dependent. is in direct opposition to the main poles. makes an angle of 90° with the main pole axis. is in the same direction as the main poles. makes an angle with the main pole axis which is load dependent. is in direct opposition to the main poles. makes an angle of 90° with the main pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Open fuse or circuit breaker. Draw too much current. Develop excessive speed and damage itself. Produce sparking at brushes. Open fuse or circuit breaker. Draw too much current. Develop excessive speed and damage itself. Produce sparking at brushes. 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 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer zero voltage regulation is achieved at a load power factor which is leading zero lagging unity leading zero lagging unity ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Induction motors provided with open slots have higher efficiency. more breakdown torque. less breakdown torque. leading power factor. higher efficiency. more breakdown torque. less breakdown torque. leading power factor. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS