Obwód

Obwód is a Polish noun with several related meanings. In geometry, obwód refers to the length of the boundary of a closed plane figure, i.e., its perimeter. The obwód of a circle with radius r is 2πr (or πd); for a rectangle with sides a and b it is 2(a+b). The perimeter is distinct from the area of a figure; it concerns the boundary length, while the area measures the size of the interior.

In electrical engineering and physics, obwód describes a closed conducting path through which electric current can flow; an electrical circuit consists of components connected to form such a loop, including sources, resistors, and capacitors. The behavior of a circuit depends on the arrangement (series or parallel) and the elements present.

In administrative and historical contexts, obwód can denote an administrative district or territorial unit, used in some regions and periods to designate a defined area for governance or organization. Today Polish usage more commonly uses terms like okręg or dzielnica for such divisions, while obwód may appear in proper names or legacy documents.

The word is also used in ordinary speech in expressions such as “na obwodzie,” meaning on the boundary or around the edge. In mathematics and science, precise use of obwód is important to distinguish it from related terms like okrąg (circle) and powierzchnia (area).