15 hardest question about DC generator?
Answers
Answer:
Not only must we be good, but we must also be good for something.” – Henry David Thoreau.
sorry I really don't knoww this answer
plz don't delete my answer already so many are deleted
Top 10 hard questions
1. The armature of a DC generator is laminated to
A. Reduce the bulk
B. Provide the bulk
C. Insulate Thakur
D. Reduce the eddy current loss
2. The field coils of DC generator are usually made of
A. Mica
B. Copper
C. Cast iron
D. Carbon
3. A DC generator may lose a residual magnetism due to
A. Heating
B. Vibrations
C. Over excitation
D.Any of the above
4. In DC generators the residual magnetism is of the order of
A. 2.5%
B. 20%
C. 15%
D. 25%
5. In DC generators the pole shoes are fastened to the pole core by
A. Rivets
B. Counter sunk screw
C.Brazing
D. Welding
6. The fall in speed of a DC generator due to increase in load can be corrected by
A. Cooling the armature
B. Increasing the excitation
C. Reducing the load voltage
D. Increasing the input to the prime mover
Explanation:
7. With the increases in field excitation of a DC generator its generated emf
A. Increases
B. Decreases
C. Remain constant
D. Increasing upto a limit and then remain almost constant
8. In DC generators current to the external circuit from armature is given through
A. Commutator
B. Solid connection
C. Slip rings
D. None of the above
9. In DC generator on no-load
A. Magnetic neutral axis moves from geometrical neutral axis in the opposite direction of rotation
B. Magnetic neutral axis coincides with geometrical neutral axis
C. Magnetic neutral axis moves from geometrical neutral axis in the direction of rotation
D. None of the above
10. In a DC generator the armature reaction results in
A. The magnetisation of the centres of poles
B. Magnetisation of Interpoles
C. Demagnetisation of the leading Pole tip and magnetisation of the trailing pole tip
D. Magnetisation of the leading Pole tip and demagnetisation of the trailing pole tip