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Light and Rainbows

Grade: 3
California, U.S.
Project done by: Siddhesvar

My Question:
How will the white light make a R a i n b o w?

Hypothesis: I think that white light is made up of many different colors.

Theory behind a R a i n b o w
Sir Issac Newton was one of the first scientists to discover that light consists of different colors.

Click on image to enlarge.
All the colors traveling together in a beam of light shine as white light. But their path is changed by the glass prism. The glass bends the differnt colors in the oight at different angles. This is called refraction

The path of each differnt color is bent by a different amount. Violet light refracts more than blue light. Blue light refracts more than green light, and so on. As a beam of white light goes through a prism, the colors separate.

Experiment 1: Reflecting R a i n b o w

Materials: Compact Disc (CD) and Flashlight.

Procedure:

1. Take a look at the blank side of the CD.
   
2. Hold the CD and shine your flashlight at the CD.
   
3. The reflected light from the CD will make different colors.

Observations: The CD surface separates white light into different colors.

Experiment 2: Prism Experiment

Materials: Glass prism and flashlight

Procedure:

1. Place glass prism and the flashligh in such a way that the light can pass through the glass prism.

2. Rotate the glass prism until the angle was right to produce different colors (spectrum).

3. Watch the different colors.

Observations: When light passes through the prism it refracts or bends often resulting in different colors.

Results: The CD and prism experiment proves that white light is made up of seven different colors.

How a R a i n b o w is formed
When the sunlight strikes a raindrop, the light is refracted.

When the light comes out of the water droplet, the sun's rays (white light) have now been split inot different colors.

In this way, each individual raindrop just behaves like a prism, refracting white sunlight into its seven component colors and a R a i n b o w is formed.

Conclusion: White light is really made up of many different colors.

The R a i n b o w we see is the result of many raindrops bending the sun rays (white light).