Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve efficiency. improve starting torque. reduce copper loss. improve power factor. improve efficiency. improve starting torque. reduce copper loss. improve power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a DC motor can be determent by Amperes law. Lenzs law. Flemings right hand rule. Flemings left hand rule. Amperes law. Lenzs law. Flemings right hand rule. Flemings left hand rule. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cross magnetization effects which of the following? commutation reduces the terminal voltage reduction in main field flux both 2 and 3 commutation reduces the terminal voltage reduction in main field flux both 2 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 10 %. 25 %. 15 %. 50 %. 10 %. 25 %. 15 %. 50 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 6 1, 3, 5 1, 2, 5 1, 4, 6 1, 2, 6 1, 3, 5 1, 2, 5 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ventilating ducts in most of DC machine are radial. longitudinal. radial as well as longitudinal. none of these. radial. longitudinal. radial as well as longitudinal. none of these. ANSWER DOWNLOAD EXAMIANS APP
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