A. Brushes should be of proper grade and size B. Brushes should smoothly run in the holders C. Smooth, concentric commutator properly undercut D. All of the above
A. Using conductor of annealed copper B. Using commutator with large number of segments C. Using carbon brushes of superior quality D. Using equiliser rings
A. Mainly to reduce the eddy currents by providing local short-circuits B. To provide path for the circulation of cooling air C. To neutralise the cross-magnetising effect of the armature reaction D. None of the above
