Electrical Machines The emf induced in the dc generator armature winding is AC and DC None of these DC AC AC and DC None of these DC AC ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce both eddy current and hysteresis loss. reduce eddy current loss only. reduce hysteresis loss only. increase the permeability. reduce both eddy current and hysteresis loss. reduce eddy current loss only. reduce hysteresis loss only. increase the permeability. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause vibrations. All of these double frequency currents in the rotor. heating of rotor. vibrations. All of these double frequency currents in the rotor. heating of rotor. 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, 4 1, 3, 5 2, 4 ,5 2, 3 , 5 1, 4 1, 3, 5 2, 4 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If dimension of all the parts of a synchorous generator and the number of field and armature turns are double, then generated voltage will change by a factor of 2. 4. 1. 8. 2. 4. 1. 8. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of induction motors the ratio of length to pole pitch for minimum cost, is taken as 1.5 to 2. 3 to 5. 1.0. 2 to 3. 1.5 to 2. 3 to 5. 1.0. 2 to 3. ANSWER DOWNLOAD EXAMIANS APP