Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.512. 0.573. 0.649. 0.443. 0.512. 0.573. 0.649. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions is a dc motor provided with compensating winding used ? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3.Wide range of rapid variation in load Select the correct answer using the codes given below : Codes : 1 and 2 2 and 3 1, 2 and 3 1 and 3 1 and 2 2 and 3 1, 2 and 3 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single-phase transformer has its maximum efficiency at 60 percent of full load. At full load copper loss will be more than core loss. equal to core loss. zero. less than core loss. more than core loss. equal to core loss. zero. less than core loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is None of these unity power factor lagging power factor leading power factor None of these unity power factor lagging power factor leading power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A flat compound generator is obtained from compound generator by connecting a variable resistor in parallel with the shunt field in parallel with the series field in series with the shunt field in series with the series field in parallel with the shunt field in parallel with the series field in series with the shunt field in series with the series field ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole dc generator is running at 1500 rpm the frequency of current in the armature winding is 150Hz. 200Hz. 50Hz. 100Hz. 150Hz. 200Hz. 50Hz. 100Hz. ANSWER DOWNLOAD EXAMIANS APP