Why the Sky is Blue

By Natalie Schafer

QuickTime™ and aTIFF (Uncompressed) decompressorare needed to see this picture.

Introduction

This power point presentation will strech your minds to the SKY with knowledge as to why the sky is blue.

Other Biggie Questions Mrs. Peck’s Physic Homepage

Have you ever wondered why the sky is blue? I was curious as to why the sky was blue opposed to any of the other colors on the visible spectrum. Why not orange? Or purple?

Science Visible Light, also known as white light, is the only part of the

electromagnetic spectrum that can be seen by the human eye.

White light has all the colors of the visible spectrum. The colors are red, orange, yellow, green blue, indigo and violet, abbreviated as Roy G. Biv. All of these colors can be shown when sunlight passes through a prism it separates the light into distinctive colors. Human’s vision responds more to green, red and blue wavelengths All the colors combined together form white light.

Newton

• He placed a triangle shaped prism in front of a beam of sunlight. On the other side of the prism showed the full color spectrum.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

• Isaac Newton was the first to discover the color spectrum

Light Scatters

• The scattering of sunlight causes the blue color of the sky

• The Nitrogen and Oxygen atoms in the atmosphere have an effect on sunlight which scatters through them

• The wavelength of the light is much larger than the particles it scatters

• Out of the three colors that respond most to the human eye; red, green and blue, blue has the longest wavelength

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Vocabulary• Visible Light- The part of the electromagnetic spectrum that your eyes can see• Scatter- To absorb sound or light and redirect the sound or light in all directions

• Frequency- The number of repetitions per unit of time of a light wave• Wavelength- The distance between one peak or crest of a wave of light and the

next corresponding peak or crest • Rayleigh Scattering- The scattering of electromagnetic radiation by particles,

resulting in the separation of colors in the color spectrum• Electromagnetic Spectrum- A full range of frequencies

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

QuickTime™ and aTIFF (Uncompressed) decompressor

are needed to see this picture.

Graph

I asked 20 adults if they knew what caused the sky to be blue.

This was there response

Why Is the Sky Blue?

0

2

4

6

8

10

12

Correct Partially Correct Incorrect

Adult Responses

Number of Responses

Related LinksThe following sites were used to learn as to why the sky

is blue.

• How Stuff Works - This website was great for an introduction of the concept as to why the sky is blue.

• Hyper Physics - This site gave me a detailed explanation to Rayleigh and Mie Scattering

• Usenet Physics FAQ - This site gave simple explanations to help gain a better understanding of the information

• Wikipedia - This site gave me a greater understanding of Rayleigh’s scattering

Biggie Questions Mrs. Peck’s Physics Homepage