Rainbow

Introduction

Summary

When white sunlight is intercepted by a drop of water, the light is diffused. As with a  prism, this diffusion separates the sunlight into its component colors.  (The “prism” in this case, would be a spherical one.) The result, when viewed at the correct angle, is a rainbow.  The observer must be between the water droplets and the Sun. Incident light is diffused back at an angle that is approximately 40° away from the angle at which  the original, incident light beam struck the droplet.

Goals

• To show the diffusion of light through a spherical raindrop.
• To explain why the colors of the rainbow occur where they do.

Features

Click on “Play” to advance through a sequence of different animations.

At the end of the last animation, rollover individual raindrops in order to observe what happens at that level.

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