Electrical Machines Which of the following represents the commutator pitch? Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the back end of the armature. The distance between the staring of first coil and its next successive coil Number of conductors spanned by one coil at the front end of the armature. Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the back end of the armature. The distance between the staring of first coil and its next successive coil Number of conductors spanned by one coil at the front end of the armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of rotating magnetic field of 8 pole 50 Hz induction motor is 750 rpm 1000 rpm 3000 rpm 1500 rpm 750 rpm 1000 rpm 3000 rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If dimension of all the parts of a synchorous generator and the number of field and armature turns are double, then generated voltage will change by a factor of 4. 8. 2. 1. 4. 8. 2. 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 3, 4, 5 2, 4, 5, 6 1, 2, 5 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the supply terminal of a DC shunt motor are interchanged The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The direction of rotation will reverse. The motor will stop. The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The direction of rotation will reverse. The motor will stop. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : For a level compounded dc generator to run at constant voltage, the series field mmf must effectively compensate 1. armature reaction mmf 2.armature resistance drop 3. brush contact voltage drop Which of these statements is/are correct ? 1, 2 and 3 1 and 3 1 and 2 2 alone 1, 2 and 3 1 and 3 1 and 2 2 alone ANSWER DOWNLOAD EXAMIANS APP
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