| 1. | As a result of armature reaction, the reduction in the total mutual air gap flux in DC generator is approximately ? | |
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40 percent
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25 percent
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10 percent
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5 percent
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Report Question| 2. | In D.C. generator the change in voltage when the load is reduced from rated value to zero, expressed as a percent age of rated load voltage, is known as ? | |
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efficiency
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regulation
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armature reactance
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loss factor
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| 3. | The slight curvature at the lower enr1 of the O.C.C. of a self-excited DC generator is due to ? | |
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high armature speed
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high field circuit resistance
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residual pole flux
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magnetic inertia
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| 4. | A shunt generator can self-excite ? | |
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only if the resistance of the field circuit is less than critical value
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only if the resistance of the field circuit is greater than critical value
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irrespective of the value of the resistance in the field circuit
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none
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| 5. | DC series generator is used ? | |
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to supply traction load
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to supply industrial Load at constant voltage
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as a booster to maintain constant voltage at the load end of the feeder
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for none of the above purpose
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| 6. | The polarity of a D.C. generator can be reversed by ? | |
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reversing the field current
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increasing field current
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reversing field current as well as direction of rotation
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any of the above
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| 7. | In a D.C. generator in case the brushes are moved so as to bring them in magnetic neutral axis, then, there will be ? | |
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demagnetisation
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cross-magnetisation
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cross-magnetisation as well as demagnetisation
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none of the above
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| 8. | ln D.C. generator, on no load ? | |
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magnetic neutral axis moves from geometrical neutral axis in the opposite direction of rotation
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magnetic neutral axis coincides with geometrical neutral axis
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magnetic neutral axis moves from geometrical neutral axis m the direction of rotation
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none of the above
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| 9. | In D.C. generators the pole shoes are fastened to the pole core by ? | |
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rivets
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counter sunk screws
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brazing
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welding
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| 10. | The bearings used to support the rotor shafts are generally ? | |
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ball bearings
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bush bearings
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magnetic bearings
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needle bearings
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