Electrical Machines The material used for commutator brushes is mostly copper. carbon. mica. cast iron. copper. carbon. mica. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the rotating losses of machine? Friction and windage losses Hysteresis losses All of the them Eddy current losses Friction and windage losses Hysteresis losses All of the them Eddy current losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to reduce eddy current losses by providing local short circuits. neutralize voltage induced in coil due to fluctuation of l None of these compensate for the decrease in speed due to increase of load. reduce eddy current losses by providing local short circuits. neutralize voltage induced in coil due to fluctuation of l None of these compensate for the decrease in speed due to increase of load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The breakdown torque of a synchronous motor varies as 1/V² applied voltage V V² 1/V 1/V² applied voltage V V² 1/V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 > I2 None of these I1 < I2 I1 = I2 I1 > I2 None of these I1 < I2 I1 = I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The emf induced in a conductor rotating in a bipolar field is DC. AC. None of these both of above. DC. AC. None of these both of above. ANSWER DOWNLOAD EXAMIANS APP