COLOR and LightFebruary 6, 2014

How does light interact with matter?

O Light can interact 3 ways:O 1. reflected – light waves bounce of

objectsO 2. absorbed – light is taken in object

(heated)O 3. transmitted – light passes through

matter

Looking through a window all 3 interactions can be observed

O How?O Seeing through glass (transmitted)O Seeing your reflection in glass

(reflected)O Feeling the heat of the glass

(absorbed)

Transparent, translucent, and opaque, what’s the difference?• Transparent – allows light to pass

through without interferenceEx. Clear glass

• Translucent – transmits light but does not transmit an image

ex. Frosted glass• Opaque – no light transmitted, can

not see throughex. Aluminum foil

How do we see colors?OOur eyes detect wavelengths of

light reflected off objectsOWhite light is made up all

colors of lightOThe color of your shirt is the

color that is being reflected not absorbed

What are the primary colors of light?

OColors of light that when mixed together equally make white light

ORed, Blue and Green lightOMixing of primary colors can

produce all other colors of light

What are the primary pigments of color?

OColors of pigments that can make all other colors

OCyan, Yellow, and MagentaOUsed in printing along with

black to make the colors of photographs

What is diffraction?O Bending of waves around barriers or

through openingsO The greatest amount of diffraction

occurs when the barrier or opening is the same size or smaller than the wavelength