Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again field winding must be excited by low voltage dc supply the field winding must be replaced the field winding connection must be reversed the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced the field winding connection must be reversed the armature connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Interpoles in a DC motor must be Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing divertor resistance of a DC series motor Increase in speed but armature currnet remains the same. Decrease in speed but armature current remains the same. Increase in speed demanding more armature current. Decrease in speed demanding less armature current. Increase in speed but armature currnet remains the same. Decrease in speed but armature current remains the same. Increase in speed demanding more armature current. Decrease in speed demanding less armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor, the speed will____ if the voltage increases, neglecting armature saturation. decrease. be unpredictable. increase remain the same. decrease. be unpredictable. increase remain the same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What does happen if tripled harmonics given to induction motor? Will results in open circuit. Nothing will happen. Fail to start. Will results in short circuit. Will results in open circuit. Nothing will happen. Fail to start. Will results in short circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Crawling in an induction motor is due to time harmonics in supply. insufficient starting torque. slip ring rotor. space harmonics produced by winding currents. time harmonics in supply. insufficient starting torque. slip ring rotor. space harmonics produced by winding currents. ANSWER DOWNLOAD EXAMIANS APP
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