Electrical Machines A shunt generator has a critical field resistance of 300 Ω at a speed of 800 rpm if the speed is raised to 1000 rpm the critical field resistance is 145 Ω. 150 Ω. 375 Ω. 225 Ω. 145 Ω. 150 Ω. 375 Ω. 225 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalanced supply voltage given to a 3 - φ, delta connected induction motor will cause all of these. less heating of the rotor. less heating of the rotor. negative sequence current. all of these. less heating of the rotor. less heating of the rotor. negative sequence current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 5 1, 4, 6 1, 2, 6 1, 3, 5 1, 2, 5 1, 4, 6 1, 2, 6 1, 3, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which one of the following statement is correct ? In an induction motor if the air gap is increased then its speed will reduce its efficiency will improve its power factor will reduce its speed will increase its speed will reduce its efficiency will improve its power factor will reduce its speed will increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC series generator, the terminal voltage with increase in load will increase gradually and then stay at rated voltage remain nearly constant decrease increase to rated voltage and then may decrease increase gradually and then stay at rated voltage remain nearly constant decrease increase to rated voltage and then may decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable moisture content of power transformer insulating oil is generally taken as 20 ppm. 35 ppm. 45 ppm. 25 ppm. 20 ppm. 35 ppm. 45 ppm. 25 ppm. ANSWER DOWNLOAD EXAMIANS APP