Electrical Machines A 4-pole DC generator runs at 1500 rpm. The frequency of current in the armature winding is: 100 Hz. Zero Hz. 25 Hz. 50 Hz. 100 Hz. Zero Hz. 25 Hz. 50 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Circle about the origin. Straight line parallel to the speed axis. Rectangular hyperbola Straight line through the origin. Circle about the origin. Straight line parallel to the speed axis. Rectangular hyperbola Straight line through the origin. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the developed torque DC Series Motor having armature resistance of 0.2 Ω and taking armature current of 60 A is connected to 250 V supply. Considered brush drop of 1 V each. 234.76 N-m. cant be determined. 133.22 N-m 266.20 N-m. 234.76 N-m. cant be determined. 133.22 N-m 266.20 N-m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In dc machines, 1. reactance voltage is proportional to armature current 2.reactance voltage is proportional to core length 3.reactance voltage is due to self-flux of the coil undergoing commutation 4. armature-cross flux is neutralized by interpolar flux 5. interpolarmmf is more than armature mmf in the interpolar zone From these, the correct answer is 1, 2, 5 1, 2, 3, 4 2, 3, 4 1, 3, 5 1, 2, 5 1, 2, 3, 4 2, 3, 4 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two identical loss less series motors connected in series across a dc supply voltage, runs at speed of N1 and N2, then ratio of their output power is N12 : N22. none. 1 : 1. N1 : N2. N12 : N22. none. 1 : 1. N1 : N2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the commutator pitch? Number of commutator segments between two successive coils. 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 conductors spanned by one coil at the back end of the armature. Number of commutator segments between two successive coils. 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 conductors spanned by one coil at the back end of the armature. ANSWER DOWNLOAD EXAMIANS APP
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