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#### Light, Prisms, and the Rainbow Connection

Did you know that the light from the sun or from white electric lights is made up of all the colors that can be seen by the human eye? In this activity you will use a prism to prove that this is true. You will find that when you shine a light in just the right way on a prism, the light enters the prism, bends (or refracts), and spreads out, showing us all of the beautiful colors of a rainbow.

The rainbows we sometimes see in the sky work in the same way. When sunlight shines on raindrops in just the right way, the sunlight is bent as it moves through the drops. It spreads out and is reflected back to us as a colorful rainbow in the sky.

The group of colors that we can see with a prism or in a rainbow is called the color spectrum. These colors always appear in the same order: red, orange, yellow, green, blue, indigo, and violet. An easy way to remember the order of colors of the spectrum is to remember the name ROY G. BIV. Each letter of the name is the first letter of a color.

Interactive Java Tutorial
 Refraction of Light See how light bends, or refracts, as it moves though different kinds of mediums.

Required Materials

• Science notebook
• Prism
• Convex lens
• Flashlight
• White paper

Activity Directions

1. Before you begin, try to guess exactly how you will make a color spectrum with a flashlight, prism, convex lens, and a piece of white paper. Answer these questions in your science notebook and then share your predictions with your partner or group.

Where on the prism should you shine the light?

Where on the paper will you see the spectrum?

2. Now use your materials to make the color spectrum appear on a piece of white paper. This works best when the room is very dark and the flashlight very bright. Can you identify all of the ROY G. BIV colors in your spectrum?

3. Compare your color spectrum with the spectrums other students have made. Which is the brightest?

4. In your science notebook, write a description of the best way to make a color spectrum with a prism. Draw a picture showing the flashlight, prism, convex lens, paper, and the color spectrum.

5. Using an encyclopedia, science books, or the Internet, find out exactly how rainbows are formed. In your science notebook, describe in writing how light moving through raindrops can make a rainbow. Include a diagram.

6. In your science notebooks, write down any questions you still have about rainbows and how rainbows are formed.

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 Newton's Prism Experiments Discover how Isaac Newton first learned that white light is made up of all the colors that we can see.

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