its a lens...1 curved edge = a circle, 1 flat surface = back, 1 curved surface = front.
(these are used in some battery-less flashlights, as an example.)
A shape with 1 vertex, 1 edge, 1 flat face, and 1 curved face is a cone. The vertex is the tip of the cone, the edge is the circular base where the flat face meets the curved surface, and the flat face is the circular base itself. The curved face extends from the base to the vertex.
A Cylinder
A football has a curved surface and polygons are flat. You can approximate a curved surface quite well if you use enough polygons but each polygon will still be flat and a football does have a curved (and rough) surface. Using a few thousand polygons you can create an approximation of a football with stitching seams and every detail but you will not have a curved surface you will have an approximation of a curved surface.
A cuboid has 6 flat faces but no curved surfaces. ..________ ./............../| /_______/.| |..............|.| |..............|./ |_______|/
A plane horizontal surface with no depth refers to a flat area on a curved surface.
curved
A shape with 1 vertex, 1 edge, 1 flat face, and 1 curved face is a cone. The vertex is the tip of the cone, the edge is the circular base where the flat face meets the curved surface, and the flat face is the circular base itself. The curved face extends from the base to the vertex.
Cylinder
Cylinder
a cone.
A Cylinder
It has a flat base, a curved surface area, a circular edge and one vertex.
Such a shape probably does not have a specific name.
A cone.
A football has a curved surface and polygons are flat. You can approximate a curved surface quite well if you use enough polygons but each polygon will still be flat and a football does have a curved (and rough) surface. Using a few thousand polygons you can create an approximation of a football with stitching seams and every detail but you will not have a curved surface you will have an approximation of a curved surface.
A sphere sliced by a plane; or a cone.
a giant or small cone