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 190 A. 240 A. 173 A. 127 A. 190 A. 240 A. 173 A. 127 A. 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 magnitude of current will decrease but the power factor will increase. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnetude of current will increase, but power factor will decrease. The magnitude of current will decrease but the power factor will increase. The magnitude will both increase. The magnitude of circuit as well as the power factor will decrease. The magnetude of current will increase, but power factor will decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Saving of copper in auto transformer is increased as compared to two winding transformer, when transformation ratio K approaches to infinity. unity. two. zero. infinity. unity. two. zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Motor for constant load torque, what will happen to the armature current if armature resistance increases? Decreases. Increases. None of above. Remain unchanged Decreases. Increases. None of above. Remain unchanged ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along neutral axis. in none of above positions. along field axis. in any of above positions. along neutral axis. in none of above positions. along field axis. in any of above positions. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor especially the cage rotors slots are nearly parallel to shaft axis. This is called crawling. skewing. slip. cogging. crawling. skewing. slip. cogging. ANSWER DOWNLOAD EXAMIANS APP