Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 > I2 None of these I1 < I2 I1 = I2 I1 > I2 None of these I1 < I2 I1 = I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC shunt generator having a wave winding supplies 50 lamps, each of 60 W at 120 V. The armature and field resistance are 0.2 Ω and 60 Ω respectively. The current in each armature conductor is 11.5 A. 27 A. 13.5 A. 23 A. 11.5 A. 27 A. 13.5 A. 23 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For which of the following loads, armature reaction is magnetizing in nature? pure capacitive load pure inductive load None of these pure resistive load pure capacitive load pure inductive load None of these pure resistive load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The demagnetising component of armature reaction in a DC generator reduces generator emf. results in sparking trouble. reduces inter poles flux density. increases armature speed. reduces generator emf. results in sparking trouble. reduces inter poles flux density. increases armature speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when commissioned after a major repair of the field system, failed to build Up voltage. It was because field system lost residual magnetism there was a break in the armature circuit field winding was wrongly connected field resistance was higher than critical resistance field system lost residual magnetism there was a break in the armature circuit field winding was wrongly connected field resistance was higher than critical resistance ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Due to magnetic saturation, the flux per pole in a DC machine without brush shift decreases in both generators and the motors with load. increases in both the generators and the motors with load. decreases in generators and increases in motor with load. increases in generators but decreases in motor with load. decreases in both generators and the motors with load. increases in both the generators and the motors with load. decreases in generators and increases in motor with load. increases in generators but decreases in motor with load. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS