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
Iron losses in a D.C. machine are independent of variations in______________? A. speedB. load C. voltage D. speed and voltage
Iron losses in a D.C. machine are independent of variations in_____________? A. speedB. load C. voltage D. speed and voltage
The armature of D.C. generator is laminated to_______________? A. reduce the bulk B. provide the bulk C. insulate the coreD. reduce eddy current loss
Laminations of core are generally made of________________? A. case iron B. carbonC. silicon steel D. stainless steel
Which of the following could be lamina-proximately the thickness of laminations of a D.C. machine ? A. 0.005 mm B. 0.05 mmC. 0.5 m D. 5 m
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 A. length of conductor B. cross-sectional area of the conductor C. number of conductorsD. all of the above
The field coils of D.C. generator are usually made of_____________? A. micaB. copper C. cast iron D. carbon
In a commutator_____________? A. copper is harder than mica B. mica and copper are equally hardC. mica is harder than copper D. none of the above