Cylinder (geometry)

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A richt circular cylinder wi radius r an hicht h.

A cylinder (frae Greek κύλινδρος – kulindros, "roller, tumbler"[1]) is ane o the maist basic curvilinear geometric shapes, the surface furmed bi the pynts at a fixed distance frae a given line segment, the axis o the cylinder. The solid enclosed bi this surface an bi twa planes perpendicular tae the axis is an aa cried a cylinder. The surface aurie an the volume o a cylinder hae been kent syne deep antiquity.

In differential geometry, a cylinder is defined mair broadly as ony ruled surface spanned bi a ane-parameter faimily o parallel lines. A cylinder whose cross section is an ellipse, parabola, or hyperbola is cried an elliptic cylinder, parabolic cylinder, or hyperbolic cylinder respectively.

The open cylinder is topologically equivalent tae baith the open annulus an the punctured plane.

References[eedit | eedit soorce]

  1. κύλινδρος, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus