## What is Curved Surface?

The curved surface is a rounded surface that is not flat.

Curved Surface | Flat Surface |

An object can have a curved surface all around it. Such objects have only one surface throughout. Examples of objects with the curved surface all around are spheres.

**Real life examples** of the objects with curved surface throughout are balls, globe, eggs, pipes, domes, etc

Egg | Ball |

There are 3D shapes that consist of only flat surfaces. For example, a cube, cuboid, pyramid and prism are all 3D shapes that are made up of flat surfaces. Their surfaces are squares, rectangles, triangles and parallelograms. None of them has a curved surface. The non-examples of 3D shapes with the curved surface are cubes, cuboids, pyramids, prisms, bricks, etc.

Pyramid | Cube |

3D shapes such as cones and cylinders have a curved surface as well as flat surfaces.

A cylinder has 2 flat surfaces and one curved surface.

A cone has one flat surface and a curved surface.

**Examples** of the objects with curved as well as flat surfaces are drums, cans, cones, etc

Can | Cone |

There are objects that can have **2 different curved surfaces**. The given image shows a test tube with a curved surface (wall: cylindrical) and a curved surface for the base (spherical) too.

Fun Facts1. Multiple circles stacked together form a curved surface. 2. Any point on a curved surface is equidistant from its centre and this distance is called the radius. 3. A flat surface can be rolled to form a curved surface, and if you open a roll, you can get a flat surface. |