why the colour of school buses is yellow
School bus yellow The color was chosen because it attracts attention and is noticed quickly in peripheral vision, faster than any other color. Scientists describe this as follows: "Lateral peripheral vision for detecting yellows is 1.24 times greater than for red."[2]
Color wheel The original color circle of Isaac Newton showed only the spectral hues and was provided to illustrate a rule for the color of mixtures of lights, that these could be approximately predicted from the center of gravity of the numbers of "rays" of each spectral color present (represented in his diagram by small circles).[7] The divisions of Newton's circle are of unequal size, being based on the intervals of a Dorian musical scale.[8] Most later color circles include the purples, however, between red and violet, and have equal-sized hue divisions.[9] Color scientists and psychologists often use the additive primaries, red, green and blue; and often refer to their arrangement around a circle as a color circle as opposed to a color wheel.[10]