It depends on the uses the lens are going to be put to. A lens may have a convex front and a flat back, or a convex front and a concave back, or even a convex surface on both front and back. Or even concave on both the front and back.
Concave means bowed inwards.
Convex means bowed outwards.
Flat surfaces: 6Curved surfaces: 0.
A cuboid has 6 flat faces but no curved surfaces. ..________ ./............../| /_______/.| |..............|.| |..............|./ |_______|/
A prism has no curved surfaces. It has 5 or more flat faces.
None. A cuboid has six flat surfaces.
A pyramid has a combination of flat and curved surfaces, but it typically consists of flat surfaces only. Specifically, a pyramid has a base that is a polygon (flat surface) and triangular faces that connect the base to a single apex, all of which are flat. Therefore, a standard pyramid has no curved surfaces. The total number of surfaces depends on the number of sides of the base polygon; for example, a square pyramid has five flat surfaces (one base and four triangular faces).
2 flat and 1 curved
Flat surfaces: 6Curved surfaces: 0.
2 flat surfaces unless it is rolled up in which case it has 2 curved surfaces.
5
A cuboid has 6 flat faces but no curved surfaces. ..________ ./............../| /_______/.| |..............|.| |..............|./ |_______|/
A prism has no curved surfaces. It has 5 or more flat faces.
A triangular prism contains zero curved and 5 flat surfaces.
None. A cuboid has six flat surfaces.
it has 0 curved faces
A pyramid has a combination of flat and curved surfaces, but it typically consists of flat surfaces only. Specifically, a pyramid has a base that is a polygon (flat surface) and triangular faces that connect the base to a single apex, all of which are flat. Therefore, a standard pyramid has no curved surfaces. The total number of surfaces depends on the number of sides of the base polygon; for example, a square pyramid has five flat surfaces (one base and four triangular faces).
it has 67 bases
a cube has 0 curved faces and 6 straight face