Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnetude of current will increase, but power factor will decrease. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnitude of current will decrease but the power factor will increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in dc machine provide ----------------- rectification? full wave controlled half wave full wave half wave controlled full wave controlled half wave full wave half wave controlled ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature resistance control method is used for the _______ ? None of these below rated speed above rated speed both 1 and 2 None of these below rated speed above rated speed both 1 and 2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Speed of alternators should be same Frequency should be same Both 1and 2 Terminal voltage is same Speed of alternators should be same Frequency should be same Both 1and 2 Terminal voltage is same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 2 pole, 12 slot synchronous machine is operating at synchronous speed. Find the slot angle? 18° 20° 30° 60° 18° 20° 30° 60° ANSWER DOWNLOAD EXAMIANS APP