Electrical Machines Flux density under trailing pole tips in case of generator will decrease either increase or decrease None of these increase decrease either increase or decrease None of these increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following alternators contain large number of poles? Aame in both alternators. Turbo alternators. Hydro alternators. None of these Aame in both alternators. Turbo alternators. Hydro alternators. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 40% 60% 38% 68% 40% 60% 38% 68% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines CRGO steel is used in the core of transformer to reduce ohmic loss. hysteresis loss. both eddy current and hysteresis loss. eddy current loss. ohmic loss. hysteresis loss. both eddy current and hysteresis loss. eddy current loss. 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 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 3, 4, 5 2, 3, 6 2, 4, 5, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A generator may loose residual magnetism due to over excitation. any of these. heating. vibrations. over excitation. any of these. heating. vibrations. ANSWER DOWNLOAD EXAMIANS APP