why is Violet apart of the light spectrum when it looks identical to purple, but purple isn’t considered part of the spectrum?

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I never knew the difference between purple and violet, all I know is that purple, pink, magenta,etc are the “colours” we see when our red and blue cones are activated at once. But Violet is considered a part of the light spectrum? They look the same to me.

In: Physics

6 Answers

Anonymous 0 Comments

Violet is a natural color which can be made by separating light with a prism.  Purple is a combination of red and blue

Anonymous 0 Comments

In music terms, Purple is more like a chord. Think a C chord. Violet is like a B note. Like, a single note. For some weird reason, when our brain hears the C chord, and the B note, it hears them exactly the same.

Anonymous 0 Comments

They’re similar, but they’re not the same. It’s like saying orange and red are identical. There is a meaningful difference in physics. Violet is a single specific wavelength of light at the lowest-wavelength end of visible light spectrum. Purple is just a combination of red and blue light. You cannot make violet by combining red and blue light and you cannot find purple in any single wavelength of light. You can use those words interchangeably in your daily life and it doesn’t really matter, but just know that they are different.

Anonymous 0 Comments

Purple and violet aren’t actually the same. Purple is violet plus red.

But yes, the difference is subtle.

Anonymous 0 Comments

It’s a quirk of your eyes’ color sensing cells. You have cells in your eyes that are sensitive to red, green and blue light. However your red sensitive cells are also a bit sensitive to light frequencies between blue and ultraviolet.

So when your eyes see those light frequencies the blue sensitive cells correctly activate but your red sensitive cells “wrongly” activate as well, making it look like red+blue (purple).

Anonymous 0 Comments

To be clear though, the difference is a definition used in specific technical disciplines. In common usage, they are just similar shades of color.

Technical fields often take words from common language and give them specific definitions for use in the field. For example, “work” has specific definitions in physics, which is force times distance. So if you’re standing still holding something heavy, you’re not doing any work in the technical sense, but it’s still work in the ordinary sense. The physics definition isn’t universally “more correct” just different.

So don’t go all “well actually” on your friend when they’re talking about painting their accent wall violet.

I’ll also point out that there are tons of colors that you can make either with a single wavelength of light OR by combining multiple wavelengths. For example, yellow can be a single wavelength between red and green, or just a mixture of red and green. This is true of most colors we see.