The output voltage of which component remains at the same polarity due to the commutator and brushes?

The armature is the component in a DC machine, such as a generator or motor, where the output voltage maintains the same polarity thanks to the commutator and brushes. The commutator serves as a mechanical switch that reverses the connection to the external circuit at the appropriate time as the armature rotates, thereby ensuring that the output voltage remains consistent in polarity. This is particularly important in DC applications where a stable and fixed polarity is necessary for proper functioning.

In contrast, the field winding creates a magnetic field that interacts with the armature, but it does not directly dictate the output voltage's polarity. The stator refers to the stationary part of a machine, which may house the field winding, while the rotor is the rotating part in general applications, which can imply an alternating current (AC) context where polarity can change. Therefore, the armature is the correct component associated with a constant polarity output due to the action of the commutator and brushes.