If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Unit: The human eye and the colourful world

Rainbows are beautiful and have been a mystery for quite a long time in the past. In this lesson, let's explore what causes them by studying the dispersion of light by prisms.
Why does dispersion happen in prism but not in window panes? How did we realize that the prism only separates white light into its constituent colors but not creates those color? In this lesson, we will explore these questions.
Twinkle twinkle little star, how I wonder what you are. Have you wondered what causes the twinkling of stars? Why don't planets twinkle? Also, why does the sun look squashed at the horizon? In this lesson, we will explore how our atmosphere is responsible for all of this.
Sometimes you can see a beam of light from car headlights, sometimes you don't, sometimes the sun is yellow, sometimes it's red, the sky is blue but the clouds are white. In this lesson, we will explore one single reason for these seemly disparate things.
This section starts with a video summarising the chapter, which is followed by an article covering CBSE board exam questions, arranged by subtopic.

About this unit

What's inside our eyes? How do they work? Why do some people wear spectacles? Why do the stars twinkle? In this chapter, we will use the rules of refraction to explore the working of our eyes and their defects. We will learn how dispersion creates rainbows and how scattering creates the blue sky.