Electrical Machines Interpoles in a DC motor must be Shunt 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. 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 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. 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 The mechanical power is developed by a DC motor is maximum when back emf is equal to half of applied voltage. none of above. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. back emf is equal to half of applied voltage. none of above. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At what power factor, the voltage regulation of a transformer can be zero ? Lagging power factor. Zero power factor. Unity power factor. Leading power factor. Lagging power factor. Zero power factor. Unity power factor. Leading power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 115 V. 200 V. 230 V. 460 V. 115 V. 200 V. 230 V. 460 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 60W 100W 80W 40W 60W 100W 80W 40W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Kh is hysteresis constant, f is supply frequency, Bm maximum flux density in core of transformer, the expression of hysteresis loss in transformer, is given by KhfBm3. KhfBm1.6. Khf2Bm1.6. KhfBm. KhfBm3. KhfBm1.6. Khf2Bm1.6. KhfBm. ANSWER DOWNLOAD EXAMIANS APP