A. direction of induced e.m.f.
B. direction of flux
C. direction of motion of the conductor if forefinger points in the direction of generated e.m.f.
D. direction of motion of conductor, if forefinger points along the lines of flux
0
According to Fleming’s right-hand rule for finding the direction of induced e.m.f., when middle finger points in the direction of induced e.m.f., forefinger will point in the direction of____________?
0
In a commutator_____________?
A. motion of conductor
B. lines of force
C. either of the above
D. none of the above
0
The field coils of D.C. generator are usually made of_____________?
A. copper is harder than mica
B. mica and copper are equally hard
C. mica is harder than copper
D. none of the above
0
The resistance of armature winding depends on
A. mica
B. copper
C. cast iron
D. carbon
0
The commutator segments are connected to the armature conductors by means of___________?
A. length of conductor
B. cross-sectional area of the conductor
C. number of conductors
D. all of the above
0
Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine ?
A. copper lugs
B. resistance wires
C. insulation pads
D. brazing
0
Laminations of core are generally made of________________?
A. 0.005 mm
B. 0.05 mm
C. 0.5 m
D. 5 m
0
The armature of D.C. generator is laminated to_______________?
A. case iron
B. carbon
C. silicon steel
D. stainless steel
0
Iron losses in a D.C. machine are independent of variations in_____________?
A. reduce the bulk
B. provide the bulk
C. insulate the core
D. reduce eddy current loss
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