This was the question on a Physics forum that I regularly read.
Purple and Violet look the same to me
You make Purple by mixing Blue and Red Paint, Right
The answer(s) have as much to do with Semantics/Human Eye Physiology as it does Physics definitions.
I'm familiar with Red, Green, and Blue being used as primary colors on TV sets, monitors, etc. This is "largely" due to the fact the Cones in the eye are "Primarily", red, green, or blue(but maybe more purple) sensitive.
We "see" only a small part of the electromagnetic spectrum, the parts we see are "percieved"(sometimes "incorrectly") as color.
"Violet" is defined in the spectrum as roughly 400 Nanometers(nm) in Wavelength.
When I mix Blue Paint(450 nm) and Red Paint(700nm), how do I get Violet/Purple (400nm)
The answer is you CAN'T
For various cone sensitivity reasons, the eyes tell us Purple/Violet when it really should'nt.
Anyway, my Physics Nerd Self found the "eyes" misinterpretation with Purple/Violet interesting,(Hopefully you might) almost along the lines of the "Matrix", are you "really" sure about what you are seeing
Here are more links about Color and Cone Physiology/Sensitivity:
Reception of Photons in the Eye: Rods and Cones
Theory of color
Blue is not primary; violet is primary
Purple and Violet look the same to me

You make Purple by mixing Blue and Red Paint, Right

The answer(s) have as much to do with Semantics/Human Eye Physiology as it does Physics definitions.
I'm familiar with Red, Green, and Blue being used as primary colors on TV sets, monitors, etc. This is "largely" due to the fact the Cones in the eye are "Primarily", red, green, or blue(but maybe more purple) sensitive.
We "see" only a small part of the electromagnetic spectrum, the parts we see are "percieved"(sometimes "incorrectly") as color.
"Violet" is defined in the spectrum as roughly 400 Nanometers(nm) in Wavelength.
When I mix Blue Paint(450 nm) and Red Paint(700nm), how do I get Violet/Purple (400nm)

For various cone sensitivity reasons, the eyes tell us Purple/Violet when it really should'nt.
Anyway, my Physics Nerd Self found the "eyes" misinterpretation with Purple/Violet interesting,(Hopefully you might) almost along the lines of the "Matrix", are you "really" sure about what you are seeing

Here are more links about Color and Cone Physiology/Sensitivity:
Reception of Photons in the Eye: Rods and Cones
Theory of color
Blue is not primary; violet is primary
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