Electrical Machines The material used for commutator brushes is mostly carbon. mica. cast iron. copper. carbon. mica. cast iron. copper. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for parallel operation of alternators? Speed of alternators should be same Both 1and 2 Terminal voltage is same Frequency should be same Speed of alternators should be same Both 1and 2 Terminal voltage is same Frequency should be same ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing equalizer rings. graphite brushes. commutator with large number of segments. carbon brushes. equalizer rings. graphite brushes. commutator with large number of segments. carbon brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and the flux of a DC motor are held constant and voltage applied across its armature is increased by 5%, the speed of the motor will increase by 5 %. remain unchanged. depend on other factors. reduce by 5 %. increase by 5 %. remain unchanged. depend on other factors. reduce by 5 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole wave wound dc motor having flux per pole of 9.56 X 10-3 Wb contains 460 armature conductors. Calculate the back emf produced when it is running at a speed of 1500 rpm. 230 volt. 440 volt. 220 volt. 240 volt. 230 volt. 440 volt. 220 volt. 240 volt. 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 KhfBm1.6. KhfBm3. KhfBm. Khf2Bm1.6. KhfBm1.6. KhfBm3. KhfBm. Khf2Bm1.6. ANSWER DOWNLOAD EXAMIANS APP