1. 18.1 Light and Color Pg

2. When Light Strikes an Object
When light strikes an object, the light can be reflected, transmitted, or absorbed
Most objects can be classified into three different categories
1. Transparent
2. Translucent
3. Opaque

3. Transparent Materials
Transmits most light that strikes it
Light passes right through without being scattered
Transparent materials allow you to see clearly what is on the other side
Examples: Clear glass, water, air

4. Translucent Materials
Scatters light as it passes through
Can see things behind a translucent object, but the details are blurred
Examples: Wax Paper & Frosted Glass

5. Opaque Materials Reflects or absorbs all of the light that strikes it
Light CANNOT pass through
Cannot see through opaque objects
Examples: Wood, Metal, tightly woven fabric

6. The Colors of Objects The color of an object depends on two things
1. The material the object is made from
2. The color of light striking the object

7. Color of Opaque Objects
Depends on the wavelengths of light that the object reflects
The color of an opaque object is the color of the light it reflects
Objects can appear to change color if you view them in different colored lights.

8. Color of Transparent and Translucent Objects
The color of transparent and translucent objects is the color of light it transmits
Transparent and translucent materials are used to make color filters
Example: Lenses in sunglasses are color filters

9. Combining Colors
Three colors that combine to make any other color are called primary colors
Red, Green, Blue
Two primary colors that combine in equal amounts produce secondary colors

10. Mixing Colors of Light
When the 3 primary colors are combined in equal amounts, they produce white light
If they are combined in different amounts they create other colors
Examples:
Red + Green = Yellow Red + Blue = Magenta

11. Mixing Colors of Light
Any two colors that combine to create white light are called complementary colors
Examples: Yellow and Blue or Cyan and Red
A color television produces many colors using only the three primary colors of light
By varying the brightness of each colored bar, the TV can produce thousands of colors

12. Mixing Pigment Inks, paints, and dyes have pigments
Pigments are colored substances that are used to color other materials
Pigments absorb some colors and reflect others
As pigments are added together, fewer colors of light are reflected and more are absorbed
The more pigments that are combined the darker the mixture looks

14. Mixing Pigments
Primary colors of pigments are: Cyan, yellow, and magenta
These colors combined in equal amounts produce black
If you combine two primary colors of pigment = secondary pigments
The secondary colors of pigments are red, green, blue