Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. R2 = sX2. R2 = s2X2. R2 = s2X2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For 250 volt DC Shunt Motor the armature and field resistance are 0.5 ohm and 250 ohm respectively. What will be the back e.m.f. produced when it takes a load current of 21A. 280 V. 150 V. 240 V. 220 V. 280 V. 150 V. 240 V. 220 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous reactance( Xs) is the combined reactance due to armature reaction and leakage flux reactance due to leakage flux reactance either due to armature reaction or leakage flux reactance due to armature reaction of the machine combined reactance due to armature reaction and leakage flux reactance due to leakage flux reactance either due to armature reaction or leakage flux reactance due to armature reaction of the machine ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is minimized by laminating the core of a transformer? Eddy current loss. Hysteresis loss. Stray loss. Copper loss. Eddy current loss. Hysteresis loss. Stray loss. Copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the residual magnetism is of the order of 10 %. 15 %. 2.5 %. 20 %. 10 %. 15 %. 2.5 %. 20 %. ANSWER DOWNLOAD EXAMIANS APP