In D.C. generators, current to the external circuit from armature is given through_____________?
A. commutator
B. solid connection
C. slip rings
D. none of above
D.C. Generators
Iron losses in a D.C. machine are independent of variations in______________?
Iron losses in a D.C. machine are independent of variations in______________?
A. speed
B. load
C. voltage
D. speed and voltage
Iron losses in a D.C. machine are independent of variations in_____________?
Iron losses in a D.C. machine are independent of variations in_____________?
A. speed
B. load
C. voltage
D. speed and voltage
The armature of D.C. generator is laminated to_______________?
The armature of D.C. generator is laminated to_______________?
A. reduce the bulk
B. provide the bulk
C. insulate the core
D. reduce eddy current loss
Laminations of core are generally made of________________?
Laminations of core are generally made of________________?
A. case iron
B. carbon
C. silicon steel
D. stainless steel
Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine ?
Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine ?
A. 0.005 mm
B. 0.05 mm
C. 0.5 m
D. 5 m
The commutator segments are connected to the armature conductors by means of___________?
The commutator segments are connected to the armature conductors by means of___________?
A. copper lugs
B. resistance wires
C. insulation pads
D. brazing
The resistance of armature winding depends on
The resistance of armature winding depends on
A. length of conductor
B. cross-sectional area of the conductor
C. number of conductors
D. all of the above
The field coils of D.C. generator are usually made of_____________?
The field coils of D.C. generator are usually made of_____________?
A. mica
B. copper
C. cast iron
D. carbon
In a commutator_____________?
In a commutator_____________?
A. copper is harder than mica
B. mica and copper are equally hard
C. mica is harder than copper
D. none of the above