Electrical Machines What type of dielectric material is used in capacitors used for fans and for power factor correction? Glass. Mica. Oil impregnated paper. Vacuum. Glass. Mica. Oil impregnated paper. Vacuum. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 4 ,5 2, 3 , 5 1, 3, 5 1, 4 2, 4 ,5 2, 3 , 5 1, 3, 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC motor is laminated to reduce the mass. to reduce the eddy current loss. to reduce the inductor. to reduce the hysteresis loss. to reduce the mass. to reduce the eddy current loss. to reduce the inductor. to reduce the hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at leading power factor. lagging power factor. any of the above. unity power factor. leading power factor. lagging power factor. any of the above. unity power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature flux is.............with respect to main field flux or main field poles? stationary None of these rotates opposite direction rotates same direction stationary None of these rotates opposite direction rotates same direction ANSWER DOWNLOAD EXAMIANS APP