Colors in Nature

Dispersion of Light in a Prism Colors separate Violet has the highest ƒ

(shortest λ), therefore it disperses the most because it interacts the most with the glass molecules.

Dispersion- the separation of white light according to its colors (frequencies)

The Atmosphere Surrounding the Earth Light travels through

millions of meters of nothingness until it starts to encounter the earth’s atmosphere

Gas Composition of Earth's atmosphere:

Nitrogen -78% of atmosphere

Oxygen - 21% of atmosphere

Trace gases -1% - Neon, Helium, Hydrogen, Methane, Carbon Dioxide

What happens to sunlight when it first encounters Nitrogen and Oxygen molecules

The Surface of the Moon (where there is no atmosphere)

Scattering of Light by Molecules(Why the Sky is Blue)

Nitrogen and Oxygen are relatively small molecules. The lower frequencies of light (red, orange, yellow) are not affected by the tiny molecules. Violet gets scattered the most, indigo next and then blue. Our eyes are more sensitive to blue, so we see the sky as being blue, not violet.

Why are Sunsets and Sunrises Orangish-Red?

How are Rainbows Formed?

Recall: Dispersion 2 Conditions needed

for a rainbow1) Sun in one part of the sky2) Rain in another part

of the sky

….and You in Between!

According to one unknown child……….

COLOR

The Color Spectrum… All color is a derivative of white light!!

Vocabulary

Dye – a molecule that absorbs certain wavelengths of light and transmits or reflects other.

Pigment – (like dye only larger) is a colored material that absorbs certain colors and transmits or reflects others

Color vs. PigmentColor by

Addition (Light) Add all colors of light… get white

Subtraction (Pigment) Dye absorbs certain wavelengths… That is to say it “subtracts” them Add dye… subtract color

Primary Colors

Primary Colors – They lied! RED GREEN BLUE

Secondary Colors Cyan Magenta Yellow

Primary Pigments

Primary Pigments Cyan Magenta Yellow

Secondary Pigments RED GREEN BLUE

Homework

Read 28.1 – 28.6 Complete Page 12 of Packet.

(Do NOT do # 26)