The electrons within atoms are the sources of all light

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

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

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.

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.

Fluorescent light without phosphors

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

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

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

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

Reflects light from another source Moon

All light can pass through

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

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

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

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

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?

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

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