EQ: How does light interact with matter? Light and Color EQ: How does light interact with matter?

EQ: How does light interact with matter? Light and Matter Three ways light interacts with matter Reflection Absorption Transmission Example – Window You can see objects outside because light is transmited through the glass EQ: How does light interact with matter?

EQ: How does light interact with matter? Transmission Passing of light through matter Transmission of light occurs all the time, through air EQ: How does light interact with matter?

EQ: How does light interact with matter? Example – Window You can see objects outside because light is transmitted through the glass You can see the glass and your reflection in it because light is reflected off the glass The glass feels warm when you touch it because some light is absorbed by the glass EQ: How does light interact with matter?

EQ: How does light interact with matter? Vocabulary Transparent – a material that transmits light. Light passes through it allowing you to see what is on the other side EQ: How does light interact with matter?

EQ: How does light interact with matter? Translucent A material that scatters light as it passes through it. Only some light passes through the material EQ: How does light interact with matter?

EQ: How does light interact with matter? Opaque A material that reflects or absorbs all of the light that strikes it. You cannot see through it EQ: How does light interact with matter?

EQ: How does light interact with matter? How do we see color? We see different wavelengths of light as different colors Long wavelengths as red Short wavelengths as violet Certain combinations of color like pink and brown are seen when certain combinations of wavelengths are present EQ: How does light interact with matter?

EQ: How does light interact with matter? Color of an Object The color that an object appears to be is determined by the wavelengths that reach your eye Light reaches your eye after being reflected or after being transmitted through an object Your brain interprets the color EQ: How does light interact with matter?

Colors of Opaque Objects When white light strikes an opaque object, some colors are absorbed and some are reflected. Only the reflected light reaches your eyes and is detected The color of light reflected by an opaque object determine the color you see. EQ: How does light interact with matter?

Colors of Transparent and Translucent Object When you look through colored transparent or translucent objects, you see the color of light that was transmitted through the object. The other colors were absorbed EQ: How does light interact with matter?

EQ: How does light interact with matter? Mixing Colors of Light Primary colors of light red, blue, green when these three colors of light are mixed the light appears white EQ: How does light interact with matter?

EQ: How does light interact with matter? Color Addition Combining colors of light Secondary color of light When two primary colors of light are combined Cyan = blue + green Magenta = blue + red Yellow = red + green EQ: How does light interact with matter?

Light and Color Television Color tv is produced by color addition of the primary colors of light TV screen made up of tiny dots of red, blue and green Each dot glows when hit by an electron beam The colors given off by the glowing dots add together to produce all the colors on the screen EQ: How does light interact with matter?

Mixing Colors of Pigment Pigment – a material that gives a substance its color by absorbing some colors of light and reflecting others Almost everything contains pigment Chlorophyll – plant pigment Melatonin – gives us our skin color EQ: How does light interact with matter?

EQ: How does light interact with matter? Color Subtraction Mixing pigments is called color subtraction Primary pigments: yellow, cyan, and magenta They can be combined to produce any color Every color in your book was produced by using the primary pigments and black ink (used for contrast) EQ: How does light interact with matter?

Class Work and Homework EQ: How does light interact with matter? Fill In What did I learn Confused Say Read the passage online “Light and Color” Answer questions 1-11 Section Review