Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 50 Hz 25 Hz 100 Hz 0 Hz 50 Hz 25 Hz 100 Hz 0 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The stator core of a 3 - Φ induction motor is laminated in order to reduce the weight of the stator. hysteresis loss. eddy current loss. both of the above. weight of the stator. hysteresis loss. eddy current loss. both of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two single-phase alternators operating in parallel have induced EMFs on open circuit of 230∠0° and 230∠10° volts and respective reactance of j2 Ω j3 Ω calculate the terminal voltage 200 V. 223.V. 150 V. 300 V. 200 V. 223.V. 150 V. 300 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 500 V, 120 KW, 50 Hz, star connected synchronous motor operating at 0.8 power factor leading has full load efficiency of 91%. The armature resistance is equal to 0.08Ω. The magnitude of armature current is nearly equal to 173 A. 240 A. 190 A. 127 A. 173 A. 240 A. 190 A. 127 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to presence of commutator. high resistance of carbon brushes. reactance voltage. armature reaction. presence of commutator. high resistance of carbon brushes. reactance voltage. armature reaction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 1, 2, 3, 4 and 5 2, 3, 4, 5 1, 3, 4, 5 2, 3, 4 1, 2, 3, 4 and 5 2, 3, 4, 5 1, 3, 4, 5 2, 3, 4 ANSWER DOWNLOAD EXAMIANS APP