Electrical Machines A 4-pole dc generator runs at 1500 rpm. The frequencyof current in the armature winding is 100 Hz 50 Hz 0 Hz 25 Hz 100 Hz 50 Hz 0 Hz 25 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, 1. physically, the brush axis is along the direct axis 2. physically, the brush axis is along the interpolar axis 3. schematically, the brush axis is along the direct axis 4. schematically, the brush axis is along the quadrature axis 5. armaturemmf is directed along the brush axis From these, the correct statements are 1 , 3, 5 2, 3, 5 1, 4,5 2, 4, 5 1 , 3, 5 2, 3, 5 1, 4,5 2, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following load normally needs starting torque more than rated torque? Centrifugal pumps. Air compressors. Blowers. Conveyers. Centrifugal pumps. Air compressors. Blowers. Conveyers. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 1, 4 2, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5 Ω and back emf of 200 V is 40 A. 44 A. 440 A. 400 A. 40 A. 44 A. 440 A. 400 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Rectangular hyperbola Straight line through the origin. Straight line parallel to the speed axis. Circle about the origin. Rectangular hyperbola Straight line through the origin. Straight line parallel to the speed axis. Circle about the origin. ANSWER DOWNLOAD EXAMIANS APP
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