# eli5:How come one end of light wavelengths is red and one violet, not black and white?

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eli5:How come one end of light wavelengths is red and one violet, not black and white?

In: Physics

Because red and violet is how our vision interprets frequencies of light, and black and white is how it interprets light intensity.

Because white is a combination of all of the visible wavelengths and black isn’t any light at all.

Colors are the result of different wavelengths of light. White and black are all or nothing. It makes zero sense to talk about black and white when discussing wavelength

White isn’t a single color, it’s what we see when red, green and blue (the primary spectral colors that our eyes detect) are mixed together.

Now off the red end of the spectrum is infrared, and off the violet end is ultraviolet. Our eyes can’t see those wavelengths of light, so you could argue that the visible spectrum actually starts and ends with black…

Color is how our brain interprets the presence and absence of various frequencies of light.

Some colors correspond to light of a certain frequency, while others do not.

If you go though all the frequencies of the visible spectrum you will see it start with red at one end and end with violet at the other.

If you have something that emits or reflects all the frequencies of light we can see in more or less equal measure it will appear white.

If you have something that doesn’t emit or reflect any visible light at all it will appear black.

to simplify all that. White is what you get when you have light in all colors and black if what you get if you light of no color and the spectrum from red to violet is what you get if you sort all the colors my frequency/wavelength.