Winter Break Blog: Rianbows, Mirages, Color of Sky

Physics Explained

Rainbows:

White light is a combination of many colors; a rainbow is when the white light has all of its colors separated. To form a rainbow the white light from the sun hits the raindrops and then reflects off the side of the raindrops and exits into your eyes. Each angle has a different distinct color.

Color of Sky:

The sky is scattered sunlight whose particles are smaller than the wavelength of the light. The sky is actually not only blue, it has many other colors in it as well; just the eye are the most sensitive to blue and not so much violet, and most of the light in the sky is violet and blue, therefore, creating the blue image in the sky. A further explanation as to why the sky is the color blue is because of the preferential scattering of short wavelength blue light compared to the scatter of long wavelength of red light, which is proportional with the gases in the atmosphere to the scattering of light by individual molecules (Rayleigh scattering).

Mirages:



The effect that two air levels at different temperatures is a mirage. Light can be refracted; considering there are two different temperatures of air and cold air is denser than hot air is. The specific type of mirage known as the oasis mirage happens when the air just about the ground is heated by the ground. A real example of this is when you believe to see the asphalt ground as water. This appears like this because the black color of the asphalt heats up the above air fast, which creates the refraction of the light from the sky. Light is refracted many times if there are numerous amounts of layers of different temperature air. As a result to this, natural objects can appear to look like city buildings. An example of this type of mirage is the Alaskan City Mirage.

Works Cited

"Light and Optics." Patterns in Nature 2000 March 3, 2008 http://acept.la.asu.edu/PiN/rdg/rainbow/rainbow.shtml#top.

"What Causes a Rainbow?." 2000 March 3, 2008 http://www.howstuffworks.com/question41.htm.

"Blue Skys and White Clouds." Patterns in Nature 1999 March 3, 2008 http://acept.la.asu.edu/PiN/rdg/sky/sky.shtml.

"Mirages in The Sky." 1998 March 3, 2008 .