Electrical Machines In dc machines, the space distribution of air-gap flux density wave at no load is rectangular co- sinusoidal flat-topped sinusoidal rectangular co- sinusoidal flat-topped sinusoidal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only 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 1, 3, 5 1, 4 2, 4 ,5 2, 3 , 5 1, 3, 5 1, 4 2, 4 ,5 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At what power factor, the voltage regulation of a transformer can be zero ? Lagging power factor. Leading power factor. Zero power factor. Unity power factor. Lagging power factor. Leading power factor. Zero power factor. Unity power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A compound motor has only shunt field winding. tertiary winding. both shunt and series field winding. only series field winding. only shunt field winding. tertiary winding. both shunt and series field winding. only series field winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In Ward-Leonard method of speed control, the direction of rotation of motor is reversed usually reversing the connection of the generator armature terminal. motor field terminal. motor armature terminal. generator field terminal. generator armature terminal. motor field terminal. motor armature terminal. generator field terminal. ANSWER DOWNLOAD EXAMIANS APP
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