Match List–I with List–II :
List—I (Colour)
a. Magenta
b. Teal
c. Mauve
d. Cyan
List—II (Combination)
1. Green and blue
2. Red and blue
3. Blue, green and white
4. Blue, red and white
Select the corre

Question

Match List–I with List–II :
List—I (Colour)
a. Magenta
b. Teal
c. Mauve
d. Cyan
List—II (Combination)
1. Green and blue
2. Red and blue
3. Blue, green and white
4. Blue, red and white
Select the correct answer using the codes given below.

UnlockIAS · Accepted Answer

Correct — A, a-2, b-3, c-4, d-1. Two of the four pairings are settled by colour theory and carry the whole question. In the additive (RGB) model used by every screen, the three primaries of light are red, green and blue, and mixing them in pairs gives the three secondaries: red and green give yellow, green and blue give cyan, red and blue give magenta. Magenta sits exactly midway between red and blue on the colour wheel and is the complement of green — mix magenta light with green light and you get white. So magenta must take item 2, 'Red and blue', and cyan must take item 1, 'Green and blue'. Yellow, the third secondary, has been left out of the list precisely so that these two cannot be confused with it. Those two pairings alone eliminate options (c) and (d), and the two that survive, (a) and (b), already agree on them — so the entire question reduces to whether teal takes item 3 and mauve item 4, or the other way round. One word decides it. Item 3 contains green and item 4 contains red. Teal is a dark cyan, named after the blue-green stripe on the head of the Eurasian teal duck (Anas crecca), so it belongs to the green side and takes item 3. Mauve is a pale purple, named after the mallow flower, sitting on the red-blue axis with no green in it at all, so it takes item 4 — and 'Blue, red and white' is in fact a textbook description of mauve, since a pale purple is exactly a red-blue mix lightened. That gives magenta 2, teal 3, mauve 4, cyan 1, which is the sequence 2, 3, 4, 1 — option (a).

Why the other options are wrong — (b) This is the only serious rival and the reason the question is worth attempting rather than guessing. It gets both certainties right — magenta as red and blue, cyan as green and blue — and then swaps the remaining two, making teal 'Blue, red and white' and mauve 'Blue, green and white'. Both halves of that swap are wrong in the same way: teal is a blue-green and cannot be described without green, while mauve is a pale purple and contains no green at all. If you can only remember one thing here, remember that teal is the green one.  (c) This makes magenta 'Blue, red and white' and cyan 'Blue, green and white' — that is, it turns both of the fully saturated secondary colours into pale tints. Magenta and cyan are produced by two primaries at full intensity, with no white added; the moment white is mixed in you have moved to pink or to a pale sky blue. It also gives teal 'Red and blue', which has no green in it, so this option fails on three of its four pairings.  (d) This pairs magenta with 'Blue, green and white', which is the one combination magenta can never be: green is magenta's complementary colour, the colour it is defined against, and magenta light plus green light gives white. It then gives teal 'Blue, red and white', again removing the green from a blue-green. Only its cyan pairing survives, and one right pairing out of four is not enough to rescue the code.

Concept: Colour mixing follows two different rule sets and most confusion comes from mixing them up. Additive mixing applies to light: the primaries are red, green and blue, pairs of them make the secondaries yellow, cyan and magenta, and all three together make white. This is how screens work, because a display emits light. Subtractive mixing applies to inks and pigments, which work by absorbing light rather than emitting it: here the primaries are cyan, magenta and yellow, pairs of them make red, green and blue, and all three together make a muddy near-black, which is why printers add a fourth ink, black or 'key', giving CMYK. The two systems are mirror images — each additive secondary is a subtractive primary, and vice versa. On top of the hue itself sit three modifications that explain the rest of the list: adding white to a hue gives a tint, adding black gives a shade, and adding grey gives a tone. Mauve is a tint of the red-blue region — a pale purple. Teal is a shade of cyan — cyan mixed with black or grey. That is the vocabulary the question is testing through the back door. Two further points make the system stick. First, the reason there are three primaries at all is physiological: the human retina carries three kinds of cone cell, sensitive to long, medium and short wavelengths, so any colour we can see can be reproduced by feeding those three receptors in the right proportion — colour television and computer displays are built directly on that fact. Second, the names of these colours are historical accidents rather than technical coinages: magenta and mauve are both nineteenth-century aniline dyes, teal is a duck, and cyan comes from the Greek kyanos for a dark blue. Knowing where a colour name comes from is often the fastest way to remember which family it belongs to, which is exactly the trick this question rewards.

State PCS 2023 Q40 — Science & Technology PYQ with Answer

State PCS 2023 Q40 — Science & Technology PYQ with Answer