A tube is a two-dimensional surface constructed by creating a prism with a hollow circle as the base. It can also be considered as a two-dimensional version of the torusconstructed by stretching a line segment in a ring.
Another way to construct it topologically is to take a sphere and then remove two disjoint open discs.
A tube can also be embedded in a two dimensional plane. This less symmetric embedding is called an annulus.
Structure and Sections
- 2 circles (1D)
- 1 tube (2D)