Red + Blue = ?
Science brain teasers require understanding of the physical or biological world and the laws that govern it.
Ben, a physics teacher and Lucy, an art teacher were arguing about what color red mixed with blue makes. Ben said it made magenta but Lucy said it made purple. Who is correct?
Answer
They are both correct. The three primaries for color are red, blue and yellow. The three primaries for light are red, blue and green. When mixing colors, red + blue = purple, but when mixing light, red + blue = magenta.
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Comments
saucie   
Jan 27, 2006
| That was a good science teaser! Made me think at 4 am got my brain going thanks!  |
SPUTNIK2 
Jan 27, 2006
| nice one, thanks for the teaser Question_Mark  |
ncsu_gurl_2011
Jan 27, 2006
| i thought we learned in kindergartern that red plus blue = purple, but what do i know about science, right? |
WJSMama
Jan 27, 2006
| Good one. I got it right, but the wrong reason. I thought it had to do with the amounts of blue:red |
mmpp123
Jan 28, 2006
| Great One! I was totally stumped!  |
wizofaus 
Jan 29, 2006
| But did you know the only reasons that Red and Blue make Purple is because of they are not "pure" red and blue? Likewise for Blue and Yellow - pure blue and pure yellow paint would not give you green. |
username
Jan 31, 2006
| how easy.
i got it as soon as i finished reading it. |
curtiss82
Feb 08, 2006
| Technically, the primary colors for dyes are Cyan, Magenta, and Yellow. This can easily be proven by looking at the ink in a color printer. Mixing Yellow ink with Magenta will result in Red, mixing Cyan with Magenta will result in Blue, and mixing Yellow with Cyan will result in Green (see the relationship between the three primary colors for dyes and the three primary colors for light. If you don't, google it for a better explaination.) Since Red and Blue are created by mixing two colors, they can not be primary colors. However, Red, Blue, and Yellow are used in art as the primary color because paint is a complex mixture (as opposed to ink), and using Red and Blue works better than Magenta and Cyan when mixing paint. |
naeem_ng
Feb 14, 2006
| That was a pretty easy one. I wasn't too sure about the physics part, but thought it sounded right too.  |
smrtr_thn_u
Feb 17, 2006
| Arent magenta and purple the same thing?  |
Methlos 
Mar 12, 2006
| i'm colour blind and i didn't even know there was a colour called magenta |
Neferjeane
Mar 13, 2006
| Magenta is a light, pinkish sort of purple, for those confused. A really fun teaser, thanks.
|
winddancir
Mar 14, 2006
| Also depends on the quantity of the paint mixture.
Lots of red + little blue = Magenta!
Equal amounts = Purple! |
Question_Mark
Mar 15, 2006
| I never knew that about pigment quantities. Thanks winddancir . Well I knew that different quantities made different colors but I didn't know what makes magenta. |
calmsavior
Apr 12, 2006
| the problem's solution is exactly what i thought. many thanks for the teaser |
GeniusGod
Apr 24, 2006
| easy!!!! |
udoboy
May 26, 2006
| I want to mix paint... I take some red on one hand, I take some blue in the other hand.. and Indigo! [pun on "in they go..."] |
OldChinaHand
Jun 02, 2006
| Good teaser. Good answer.  |
dantak
Jun 17, 2006
| Ok, for those of you who care. This comes down to the difference between additive colors and subtractive colors. Paint is a subtractive color because red paint for instance absorbs all the wavelengths of light in ambient light and reflects red. Light on the other hand is additive because you when you mix light of a certain wavelength with light of another, you get back a composite of the two. Technically speaking, if you mix all the wavelengths of light in the visible spectrum you get white, and if you mix all colors of paint you get black. I say technically because if you actually mix all the colors of paint you something called chromatic grey. That was a little sceintific for some of you I'm sure but this is the science category
Tschuss |
mmmcla01
Jun 28, 2006
| I was in the same "situation" as WJSMama. I thought it had to do with the values of the colors. Oh, well, I don't know that much about science, anyway...math is so much more fun and I'm A LOT better at it  |
qwertyopiusa
Nov 29, 2006
|
dantak & curtiss82:
thanks for the accurate information! |
stil
Nov 29, 2006
| As a physics teacher, Ben should have known both answers. As would Moe, a teacher in theater arts. Moe might also mention that red light on blue paint and blue light on red paint can have the effect of seeming black. |
parayik
Mar 17, 2007
| Easy, but cool! |
ElainaNV
Apr 28, 2008
| Is that why when I get my nails done- painted black- they always seem to look Blue instead?  |
trewq
Aug 21, 2009
| nice one! i didn't get it--i guessed they were right because it wouldn't be much of a brain teaser if they weren't but i had no idea why
very fun! and very hard for me |
TableElbows
Aug 21, 2009
| Yay, got it right away! |
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