Electrical Machines Flashing of DC generator means increasing flux density by providing extra ampere-turns in field. neutralization of residual magnetism. creation of residual magnetism by a DC source. None of these increasing flux density by providing extra ampere-turns in field. neutralization of residual magnetism. creation of residual magnetism by a DC source. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Variation in speed by ward-Leonard control of DC motors occurs due to variation in Armature voltage. Supply voltage. Field excitaion. Armature current. Armature voltage. Supply voltage. Field excitaion. Armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - φ induction motor can also be referred to as a shunt motor. asynchronous motor. repulsion motor. transformer. shunt motor. asynchronous motor. repulsion motor. transformer. 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 ? 1, 2 and 5 1 and 4 2, 3 and 4 3 and 5 1, 2 and 5 1 and 4 2, 3 and 4 3 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 2166.67V, 230 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. 2166.67V, 230 rpm. 541.67V, 250 rpm. 541.67V, 200 rpm. 2166.67V, 270 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause vibrations. heating of rotor. double frequency currents in the rotor. All of these vibrations. heating of rotor. double frequency currents in the rotor. All of these ANSWER DOWNLOAD EXAMIANS APP