Electrical Machines Interpoles in a DC motor must be Series 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. 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 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. 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. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be zero. about 100 V. 250 V. very small, say about 2 or 3 V. zero. about 100 V. 250 V. very small, say about 2 or 3 V. ANSWER DOWNLOAD EXAMIANS APP
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 flux involved in the emf equation of a transformer has total value. average value. maximum value. rms value. total value. average value. maximum value. rms value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For higher values of armature, the speed of a DC series motor is Proportional to armature current. Proportional to the square of armature current. Constant. Inversely proportional to armature current. Proportional to armature current. Proportional to the square of armature current. Constant. Inversely proportional to armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a 3-phase, 4 pole, 50 Hz synchronous motor the frequency, pole number and the frequency are halved. The motor speed will be 375 rpm 1500 rpm 75 rpm 3000 rpm 375 rpm 1500 rpm 75 rpm 3000 rpm ANSWER DOWNLOAD EXAMIANS APP