Electrical Machines What is the phase difference between two windings of A.C servomotor ? 90°. 60°. 30°. 120°. 90°. 60°. 30°. 120°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A synchronous machine has P number of poles, find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm)? ωe = ωm ωe = 2/P*ωm ωe = P*ωm ωe = P/2*ωm ωe = ωm ωe = 2/P*ωm ωe = P*ωm ωe = P/2*ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions hunting of synchronous motor is likely to occur ? Small and constant load. Periodic variation of load. Over-excitation. Over-loading for long period. Small and constant load. Periodic variation of load. Over-excitation. Over-loading for long period. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A short circuit test on a transformer gives copper loss at any load. copper loss at full load. copper loss at over load. copper loss at half load. copper loss at any load. copper loss at full load. copper loss at over load. copper loss at half load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a step down transformer which one of the following statements is true? Number of secondary turns is more than that of primary. Number of secondary turns is less than primary turns. Secondary current is less than primary current. Secondary power is less than primary power. Number of secondary turns is more than that of primary. Number of secondary turns is less than primary turns. Secondary current is less than primary current. Secondary power is less than primary power. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 7. 4. 3. 12. 7. 4. 3. ANSWER DOWNLOAD EXAMIANS APP
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