Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by varying the speed. varying the applied voltage. changing the load. changing the field excitation. varying the speed. varying the applied voltage. changing the load. changing the field excitation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a single phase transformer the magnitude of leakage reactance is twice that of resistance of both primary and secondary. With secondary short circuited, the input power factor is 1/√2 2/√5 1/3 1/√5 1/√2 2/√5 1/3 1/√5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Thin laminations are used in a machine in order to reduce Eddy current losses Copper losses Both 1 and 2 Hysteresis losses Eddy current losses Copper losses Both 1 and 2 Hysteresis losses ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In most condition which frame of motor will be preferred? Open type. Drip proof. Totally enclosed fan coiled. Splash proof. Open type. Drip proof. Totally enclosed fan coiled. Splash proof. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor especially the cage rotors slots are nearly parallel to shaft axis. This is called skewing. crawling. slip. cogging. skewing. crawling. slip. cogging. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM in order to eliminate cogging the number of stator slots must be either (B) or (C). an integral multiple of number of rotor slots. equal to number of rotor slots. unequal to number of rotor slots and skewed in shape. either (B) or (C). an integral multiple of number of rotor slots. equal to number of rotor slots. unequal to number of rotor slots and skewed in shape. ANSWER DOWNLOAD EXAMIANS APP
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