Dace Vilksy age 11, of Des Moines, Iowa, for his question:
What is color?
All the colors of the rainbow come from light. This is true of the red of a rose, the green of a leaf, the brown of a dogts coat or any other color you can see. Some colors comp from the light of electricity or other lamps. But most of them ride here on sunbeams, some 93 million miles from the sun. For most of the light we see is by sunlight,
We say that ordinary light is white light because it shows no color, Actually, under normal circumstances it is colorless light. And for sunlight, normal circumstances means whizzing across space at about 186,000 miles a second. Only a very small amount of the sun's output of light strikes the earth. When that happens, the circumstances change.
The apparently colorless light is then forced to show its colors, We then see that it is made of a blend of colors, the colors of the rainbow. The rainbow has seven principal colors ‑ red, orange, yellow, green, blue, indigo and violet. But each of these blends into the next with countless midway tones and tints. Hidden in a speeding sunbeam are all the colors we will ever see or imagine.
The world around us is made of chemical substances and each chemical has its own way of doing things, ouch reacts to light in its own way. It absorbs or lets through certain colors and pounces others backs It breaks up the skein of colors in colorless light. The petal of a red rose absorbs the yellow, green anal blue rays from a sunbeam. The red rays it rejects, bouncing them back for our eyes to seep. A green leaf absorbs all but the green rays, So the green rays are bounced back for us to see. A white lily or a white sheet of paper absorbs no colors from light at all. The entire sunbeam which. Strikes these surfaces is reflected back for us to see as white.
A lump of black coal absorbs dust about all the colors of a sunbeam. All the colors of the rainbow are lost and none are reflected back for us to see. The coal looks black.
A beam of light is a form of energy, pulsing along in waves. A wave length is the distance from the crest of one wave to the crest of the next. Each strand of color in white light travels on its own wave length, longer or shorter than all the others. The violet rays travel with the shortest wave lengths, the red rays travel with the longest wave lengths. The blue and violet rays get into trouble when they strike the fine particles in the atmosphere. Because of their short wave lengths, they are bent and scattered. That is why the daytime color of the sky is blue.
The assorted wave lengths of white light are far too small to be seen as they pulse clang. Imagine the thickness of a. sheet of note paper. In this distance, the red rays pulse along in 130 waves, the violet rays pulse along in about 260 waves. And every color between, pulses along on its own special wave length.