3. The electrons within atoms are the sources of all light

4. There are four steps that electrons go through to produce light. Light is formed when... Light is formed when... 3. Fall back down, 1. Electrons gain energy, 2. Move up an energy level, 4. And release that energy

5. Photon The tiny packet or bundle of light energy that is released is called a Photon LIGHT is made up of a stream (like a wave) of photons THIS IS WHY WE SAY LIGHT CONTAINS BOTH PROPERTIES OF WAVES AND PARTICLES

7. Incandescent 1. Incandescent: light produced by a thin wire filament; energy flows through and light is given off in the form of light and heat.

8. Fluorescent 2. Fluorescent: bulb filled w/mercury gas at a low pressure. Electricity flows through, the electrons collide w/ the gas giving off UV radiation. PhosphorsPhosphors coat the bulb absorb the UV radiation and giving off the light.

9. Fluorescent light without phosphors

10. Neon 3. Neon: bulbs that glow and give off a variety of colors, depending on the type of gas it contains

11. A beam of coherent light (a single wavelength) Used in surgery Light Amplification of Stimulated Emission of Radiation

13. Def. - When waves vibrate along a single plane (sunglasses) Can you see the turtle???

14. Gives off it’s own light Ex. – The sun, light bulbs, and candles are luminous objects

15. Reflects light from another source Moon

16. All light can pass through

17. Some of the light can pass through; Ex. – Wax Paper

18. Includes materials that absorb or reflect ALL light so that no light is transmitted through

20. White light is actually all colors of the visible spectrum refracts white lightPrism: an object (usually a piece of glass) that refracts white light and separates the colors based on their different frequencies

21. Additive Colors When all three are mixed, white light is produced. Green Blue Red

22. blue and green are absorbed Apple appears red White light = mixture of colors red Because….red light is reflected!! So what determines the color of an object?

25. Subtractive (used in ink & paint) When all three are mixed, black is produced. Yellow Magenta Cyan

26. Color printers use the same principle. Look closely; there are only 3 colors of dots. Magenta, Yellow, and Cyan