Why do we see different colors?
Why does cloth look darker when it is wet?
Electromagnetic radiation is light energy. The Sun emits electromagnetic radiation, which contains gamma rays, x-rays, ultroviolet light, visible light, infrared light, microwaves, and radio waves. For now, I want to focus on one small section of the Electromagnetic Spectrum call visible light, which is a band of light energy that the human eye responds to. Rainbows show the color range of visible light: Red, Orange, Yellow, Green, Blue, Indigo, Violet. These are the colors identified by Sir Isaac Newton and the colors often found in science books. Using the first letter of each color, a mnemonic for remembering the colors in order of least to most energy is: ROY G BIV.
White light contains the entire visual light spectrum, ROY G. BIV. The photo shown has different colors. White light from the Sun struck every object you see in the photo. The black tires absorbed all of the light; The red car absorbed all of the light except red, which it reflected; My granddaughter’s shirt absorbed all of the light except blue; Shades of blue result in the blending of light energy; The green plants absorbed all of the light except green and as with other colors, various blending of light enegy produces different shades.
You can only see things because light reflects off the object to your eyes. The color of anything is due to light energy from the object traveling to your eyes. When a cloth gets wet, the water in the cloth affects the absorption and reflection of light. Since wet spots on cloth look darker, wet spots absorb more of the white light striking the cloth. When less light is reflected to your eye, that part of the cloth looks darker.
See Mission Science: Electromagnetic Spectrum for more information about Light Energy.