50. Which of the following IS Closet to the generator, armature circuit resistance of a dc
A.2 W
B. 20 W
C. 2000 W
D.200 W
51. Hysteresis losses in a dc generator are basically due to
A. current flowing in the armature
B. reversal of man coreetism of the armature core
C. initial energy to magnetise the core
D. none of these
52. Hysteresis los proportional to ses in a de machine are
A. IN
B.N
C. N2
D. 1/N2
53. Eddy current losses in as n a de machi
A. 1/t e vary
B.142
C. t
D. t2
54. A re t is the thickness of laminations de machine has of efficiency when
A. variable losses constant losses
B. variable losses --- corrTZT-
C. variable losses (constant losses)
D. none losses of these
55. The eddy current losses vary as as Hysteresis loss in a de generator varies reversal where f is the frequency of magnetic flux
A.f
B. 1/f
C.f2
D.1/j2
56.
A.
B.
C.
D.
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