Electrical Machines If the full load speed of 3-phase, 50Hz induction motor is 950 rpm, what is its half load speed nearly equals to? 950 rpm 1000 rpm 940 rpm 975 rpm 950 rpm 1000 rpm 940 rpm 975 rpm 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, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 1, 4 2, 4 ,5 1, 3, 5 2, 3 , 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following statements is/are correct ? None of these Inter pole winding will act in interpolar region. Both A and B. Compensating winding will act under the pole. None of these Inter pole winding will act in interpolar region. Both A and B. Compensating winding will act under the pole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field connection of a DC Shunt Motor is changed then it will run in same direction by slowly. motor will not run. it will run in opposite direction. it will run in same direction. it will run in same direction by slowly. motor will not run. it will run in opposite direction. it will run in same direction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic field which initially induces emf in the armature in a self excited DC generator is because of armature reaction. permanent magnets. None of these residual magnetism. armature reaction. permanent magnets. None of these residual magnetism. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.5 p.u 0.125 p.u 0.75 p.u 0.25 p.u 0.5 p.u 0.125 p.u 0.75 p.u 0.25 p.u ANSWER DOWNLOAD EXAMIANS APP
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