See A Sunset

The particles of milk in the water cut out some of the colors in the light coming from the flashlight. So only orange and red rays get through. This occurs in nature as well. When the sun is high in the sky, it generally appears white because all wavelengths of visible light reach an observer's eyes with almost equal intensity. As the sun sinks toward the horizon, sunlight enters the atmosphere at a much lower angle and consequently must pass through much more atmosphere before being seen by an observer. Air molecules scatter away the shorter wavelengths of light (violet and blue) and the only light which penetrates through the atmosphere are the longer wavelengths of light (yellow, orange and red) which produce colorful sunsets. When there is a high concentration of particles in the atmosphere that are slightly larger than air molecules (like smoke, dust, and pollutants), shorter and intermediate wavelengths of light (violet, blue and yellow) are scattered away. Therefore, only the longer wavelengths (orange and red) reach the observer's eyes, giving the sun a orange-red appearance. This is what happens with the milk particles in the water.



Lesson Plan and Standards

See a Sunset: lesson plan and standards

Extended Resources:

Meagan Hickle's Experiment on See a sunset!