Graphing the Rainbow
Students are introduced to different ways of displaying visual spectra, including colored "barcode" spectra, like those produced by a diffraction grating, and line plots displaying intensity versus color, or wavelength. Students learn that a diffraction grating acts like a prism, bending light into its component colors.
When white light enters a prism, it bends (refracts), and colors are produced. The same thing happens when sunlight hits a water droplet. The colors that result from this bent light form the rainbows that are so familiar to us.Copyright (left) National Aeronautics and Space Administration and (right) 2004 Denise W. Carlson. Used with permission.
Understanding graphs and plots is crucial to engineering, as engineering in all fields is driven by the need to obtain scientific data. Engineering methods are constantly improved and new types of engineering are created based upon the types of data needed to advance science.
After this activity, students should be able to:
- Explain that light from different sources, when passed through a prism or diffraction grating, can be separated into component colors.
- Explain the basic tools engineers use to view spectra.
- Match a "barcode" spectrum with its corresponding line plot.