Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at unity power factor. lagging power factor. leading power factor. any of the above. unity power factor. lagging power factor. leading power factor. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 10 Ω. 4 Ω. 8 Ω. 2 Ω. 10 Ω. 4 Ω. 8 Ω. 2 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the reason for stationary armature essential in alternators above 5 KVA? Insulation requirement is less. Collecting of large current is simple. All of these Operating cost is less. Insulation requirement is less. Collecting of large current is simple. All of these Operating cost is less. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 3/4. 16/9. 4/3. 9/16. 3/4. 16/9. 4/3. 9/16. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Iron losses in a DC machine are independent of variation in voltage. speed. speed and voltage. load. voltage. speed. speed and voltage. load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 1, 4 2, 4 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 ANSWER DOWNLOAD EXAMIANS APP
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