NCERT Book Class 9 Mathematics Chapter 5 I'm Up and Down, and Round and Round

I’m Up and Down, and
5 Round and Round

Humanity has always been fascinated by the shapes of the things
around them. In some early cave paintings, the sun is depicted as a
circle. In the cave paintings of Gudahandi in Odisha, one sees numerous
geometric patterns including triangles, squares, circles, and ovals.
These shapes were likely inspired by what humans saw in nature.
Can you recognise the origin of the shapes in Fig. 5.1?

Fig. 5.1

Circles form when raindrops fall on water. The cross-section of a
plant stem and the inflorescence of a sunflower are also circular in
shape. The full moon and sun also look circular.

Moon Sun (during a total solar eclipse)
Fig 5.2