Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increases in field excitation of a DC generator, its generated emf decreases. remains constant. increases. increases upto a limit and then remains almost constant. decreases. remains constant. increases. increases upto a limit and then remains almost constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The supply voltage to an induction motor is reduced by 10%. By what percentage, approximately, will the maximum torque decrease? 10% 5% 40% 19% 10% 5% 40% 19% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Iron loss in a transformer mainly occurs in winding of transformer. transformer insulating oil. iron made tank of transformer. steel core in transformer. winding of transformer. transformer insulating oil. iron made tank of transformer. steel core in 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 ? 3 and 5 1 and 4 2, 3 and 4 1, 2 and 5 3 and 5 1 and 4 2, 3 and 4 1, 2 and 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The use of double squirrel cage winding on the rotor provides a large starting torque. reduced starting torque. low noise. higher efficiency. a large starting torque. reduced starting torque. low noise. higher efficiency. ANSWER DOWNLOAD EXAMIANS APP
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