In the study called "Light: Waves and Photons," you explored the relationship between light and color. Within the visible spectrum, the shortest wavelengths of light (roughly 400 nm) are blue, and the longest wavelengths (around 700 nm) are red. These numbers represent the wavelengths of light not absorbed by compounds having these colors. For instance, a solution of copper sulfate appears blue because when it is exposed to electromagnetic radiation it transmits light with wavelengths near 400 nm and absorbs all other wavelengths. It's really the reflection of blue light, and the absence of colors at wavelengths that are far from 400 nm that our minds interpret as blue.
Now let's look at the color green. According to the visible spectrum presented in the study, green light has a wavelength of about 500 nm But does this make sense? Perhaps when you were younger and just learning to paint and draw, someone told you that yellow and blue make green. You figured out how to mix yellow and blue paints to get green paint. So is green a single wavelength or a combination of two different wavelengths?
Consider three green objects: a green sweater, the leaves on a tree, and the coating on green M & M's™. Imagine that these are all the exact same shade of green. Why are they green? Are they "pure" green or a mixture of yellow and blue? Is there any way you could tell the difference? Follow the directions below to go online and share your ideas with your classmates!
Scoring
This discussion is worth a maximum of 15 points. You'll get 10 points for participating. Your instructor will give you another 5 points if you post a follow-up comment or question that furthers the discussion.