Electrical Machines Which DC motor will have least percentage increase of input current, for the same percentage increase in the torque DC Shunt Motor Compound Wound DC Motor Separately Excited DC Motor DC Series Motor DC Shunt Motor Compound Wound DC Motor Separately Excited DC Motor DC Series Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The condition for maximum running torque is 0.707 lagging 0.5 lagging R = S.X unity zero 0.707 lagging 0.5 lagging R = S.X unity zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 3. 4. 7. 12. 3. 4. 7. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is done in speed control of DC motor by field flux control? Inserting an additional resistance in the armature circuit. Inserting resistance to armature circuit and field circuit. Inserting an additional resistance in the field circuit. Any of above. Inserting an additional resistance in the armature circuit. Inserting resistance to armature circuit and field circuit. Inserting an additional resistance in the field circuit. Any of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Increase. Remain unaltered. Reduce. Oscillate around the normal speed. Increase. Remain unaltered. Reduce. Oscillate around the normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous generator is feeding a zero power factor (lagging) load at rated current. The armature reaction is demagnetizing. magnetizing. cross – magnetizing. ineffective. demagnetizing. magnetizing. cross – magnetizing. ineffective. ANSWER DOWNLOAD EXAMIANS APP
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