Electrical Machines For a 3-phase, 4 pole, 50 Hz synchronous motor the frequency, pole number and the frequency are halved. The motor speed will be 1500 rpm 375 rpm 75 rpm 3000 rpm 1500 rpm 375 rpm 75 rpm 3000 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The compensating winding in a DC machine is located on pole shoes for avoiding the flashover at the commutator. is located in armature slots for compensation of the armature reaction. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. is located on pole shoes for avoiding the flashover at the commutator. is located in armature slots for compensation of the armature reaction. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of rotor current of 50 Hz induction motor operating at 4% slip? 1 Hz 50Hz 2HZ 2.5Hz 1 Hz 50Hz 2HZ 2.5Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two 3-phase AC generators are such that one has twice the linear dimensions of the other. The field windings of each are excited to give identical sinusoidal air-gap flux density waveform. Both have the same number of stator slots and identical winding patterns. The conductor/slot in a big generator is K times that of the smaller one. The value of K to get equal no load voltage at same frequency is 1/2. 1/4. 4. 8. 1/2. 1/4. 4. 8. 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 Which of following methods are suitable for the speed control of squirrel cage induction motor? 1. Voltage control. 2. Frequency control. 3. Pole changing method. 4. Rotor resistance control select the correct answer using the codes given below:- 1, 3 and 4. 1, 2 and 3. 2, 3 and 4. 2 and 4. 1, 3 and 4. 1, 2 and 3. 2, 3 and 4. 2 and 4. ANSWER DOWNLOAD EXAMIANS APP