In this video segment adapted from Shedding Light on Science, learn about the dispersion of light, the electromagnetic spectrum, and how sunlight contains a range of wavelengths (photons of differing energy). Isaac Newton investigated sunlight by shining it through a glass prism; after the prism refracted the light, he saw a spectrum of colors. He recognized that sunlight was made up of many colors, which could not be further separated when passed through a second prism. Drops of water in the air have the same dispersion effect. In the video, a bowl of water is used to simulate a giant raindrop to show how the differing angles of refraction of different wavelengths create rainbows.
This media asset was adapted from Shedding Light on Science.
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