1. Light Intro Video

2. Light and Color

3. Light interacting with matter
When light hits matter, at least one of three things can happen:
Reflection
When light bounces off an object
Absorption
Transfer of light energy to matter
Makes things feel warmer
Transmission
Passing of light through matter

4. What type of light interactions are taking place here?

5. Three types of materials
Transparent – matter through which light is easily transmitted (you can easily see through it)
Opaque – matter that does not transmit any light (you can’t see through it)
Translucent – matter that transmits light, but scatters it as well (you can only partially see through it)

6. How do one-way mirrors work?

7. Where do colors come from?
Remember that we see different colors of light because light waves come in different wavelengths
The longest wavelengths of visible light is seen as red
The shortest wavelengths of visible light is seen as violet
The color an object appears is determined by which wavelengths of light are able to reach your eyes, either through reflection or transmission

8. How does colorblindness work?

10. Color and opaque objects
The colors of light that are reflected by an opaque object determine the color you see
White light (the combination of all colors of light) strikes this sweater. All colors of light, except blue, are absorbed by the sweater. Blue light is reflected, so it reaches your eye and you see a blue sweater

11. What about black and white?
White objects are white because they reflect all colors of light
The presence of all light = white
Black objects are black because they absorb all colors of light
The absence of all light = black

12. Mixing Light
You don’t have to mix all colors of light to get white light
You can just add red, blue and green light together
These are the primary colors of light
Combining colors of light is called color addition

13. When you mix two primary colors of light, you get a secondary color (cyan, magenta or yellow)

14. Thanks for the compliment
Complimentary colors are two colors that create white light when shining on a surface at the same time
Ex: blue and yellow
Why are these complimentary (why do they produce white light?)
What are other examples of complimentary colors?

15. Start here on 4/18

16. Mixing Light Colors
vision_en.html

17. https://youtu.be/ksS-FJ3B8Og
Mixing Light Colors

18. What is this??? A close up of a tv screen
Tv screens are made up of little red, blue and green dots
When electrons hit them in certain combinations, you get the various colors on the screen

19. Are paint and light the same thing?
Do you get white paint when you mix all of the other colors of paint?
No! so paint and light are not the same thing
Paint colors come from pigments (materials that give substances color by absorbing some colors and reflecting others)

20. What are the secondary pigments?
The primary pigments are cyan, magenta and yellow
Every pigment absorbs at least one color of light
As you mix pigments, more colors of light are absorbed so mixing them is called color subtraction
What are the secondary pigments?

21. Summary Video

22. Brain Games: In Living Color