| 1. | Flashing the field of D.C. generator means ? | |
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neutralising residual magnetism
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creating residual magnetism by a D.C. source
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making the magnetic losses of forces parallel
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increasing flux density by adding extra turns of windings on poles
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Report Question| 2. | The generator has poorest voltage regulation ? | |
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shunt
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series
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compound
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over-compound
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| 3. | The voltage drop for which of the following types of brush can be expected to be least ? | |
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Graphite brushes
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Carbon brushes
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Metal graphite brushes
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None of the above
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| 4. | The critical resistance of the D.C. generator is the resistance of ? | |
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field
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brushes
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armature
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load
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| 5. | The number of brushes in a commutator depends on ? | |
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speed of armature
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type of winding
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voltage
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amount of current to be collected
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| 6. | If a D.C. generator fails to build up the probable cause could not be ? | |
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imperfect brush contact
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field resistance less than the critical resistance
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no residual magnetism in the generator
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faulty shunt connections tending to reduce the residual magnetism
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| 7. | A D.C. welding generator has ? | |
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lap winding
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wave moving
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duplex winding
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any of the above
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| 8. | Drop in speed of a D.C. generator due to increase in load can be compensated by ? | |
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cooling the armature
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increasing the armature resistance
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reducing the load voltage
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increasing the input to the prime mover
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| 9. | The function of pole shoes in the case of D.C. machine is ? | |
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to reduce the reluctance of the magnetic path
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to spread out the flux to achieve uniform flux density
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to support the field coil
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to discharge all the above functions
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| 10. | When the shunt field of a compound generator is connected across both the series field and armature. Such a convection is known as ? | |
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short shunt
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long shunt
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cumulative compounding
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differential compounding
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