Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Oscillate around the normal speed. Increase. Reduce. Remain unaltered. Oscillate around the normal speed. Increase. Reduce. Remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 4/3. 3/4. 9/16. 16/9. 4/3. 3/4. 9/16. 16/9. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC generator runs at 750 rpm and generate an emf of 240 V. The armature is wave wound and has 792 conductors. If the total flux from each pole is 0.0145 Wb. What is the leakage co-efficient? 1.4. 1.5. 1.8. 1.2. 1.4. 1.5. 1.8. 1.2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field divertor method of speed control of a DC series motor gives speed above rated one due to reduction of Field current. Armature current. None of above. Line current. Field current. Armature current. None of above. Line current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a three phase star - delta transformer, what is the angle difference between primary and secondary phase voltages? Delta side leads by 30°. Delta side lags by -30°. Star side leads by 30°. Star side lags by -30°. Delta side leads by 30°. Delta side lags by -30°. Star side leads by 30°. Star side lags by -30°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole wave wound dc motor having flux per pole of 9.56 X 10-3 Wb contains 460 armature conductors with armature resistance of 0.6 ohm. Calculate the starting current flowing through the armature if the supply voltage is 240 volt. 320 Amp. 800 Amp. 0.5 Amp. 400 Amp. 320 Amp. 800 Amp. 0.5 Amp. 400 Amp. ANSWER DOWNLOAD EXAMIANS APP