The Pigments Of An Object Determines Its Color
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The Pigments Of An Object Determines Its Color

"Come here Tee. Since you know light, explain to me in simple terms, how pigments determine the color of an object". Said Tee's mom. "Ok mom". Said Tee, a sharp 7 year old.

Describe Tee's explanation.

The strings: S7P2A21 (Identity - Physical Property)

The math:
Pj Problem of Interest is of type identity (physical property). Color is a property of matter that is used to identify matter.

Visible light is a continuous spectrum of light (red, orange, yellow, green, blue, indigo, violet). Each component of light in the visible light spectrum has its characteristic color associated with its unique wavelength. The color of light, range from red to violet in decreasing magnitude of wavelength (increasing magnitude of frequency). There is an infinite number of light colors in the visible light spectrum. Fortunately, any of these colors can be derived from the mixing in approriate proportions, of only three light colors: red, green and blue (figure 22.5a). Consequently, the colors red, green and blue (rgb) are called primary colors.

Light that strikes matter can be transmitted, absorbed or reflected. The matter is transparent if it transmits light readily (e.g. water, air, glass). The matter is translucent if it scatters the light it transmits (e.g.wax paper, frosted glass). The matter is opaque if it does not transmit light (e.g. a sheet of metal, block of wood, black cloth). The color of an opaque object is the color of the light it reflects. This is because the light absorbed by the object is in the object and does not reach the eyes. When all the colors of the visible spectrum are reflected, the eyes perceive the color white. When all the colors of the visible spectrum are absorbed, the eyes perceive the color black.

Pigments are substances that selectively absorb visible light of certain wavelengths. A pigment absorbs at least one color of light out of the visible spectrum of light that strike it. The light not absorbed are reflected and they determine the pigments color. There are natural pigments (e.g. chlorophyll in the green leaves of plants and haeme in blood) and synthetic pigments. Readily available pigments are mostly compounds of metal (e.g. titanium oxide, iron oxide, chromium oxide). The number of colors absorbed by pigments can be increased by the successive mixing of pigments. This in essence reduces the number of colors from the visible spectrum available for reflection. Pigments of various colors can be produced from pigment mixing. The primary pigments are cyan, magenta and yellow (figure 22.5b) and when mixed in equal amounts, results in black because the mix absorbs all colors.

All objects contain pigments. So, when visible light strikes an object, the light reflected will depend on the light absorbed by the pigments. Since the color of an object is the color of the reflected light, the color of an object is a result of the pigments it contains.

Blessed are they that have not seen, and yet have believed. John 20:29