Transcript Slide 1

18.4 Color
Separating White Light Into Colors
How does a ___________ separate white
light?
As white light passes through a prism,
shorter wavelengths ___________ more than
longer wavelengths, and the colors
_______________.
18.4 Color
Separating White Light Into Colors
Sunlight is made up of all the ___________ of the
visible spectrum. A prism separates white light into a
visible spectrum.
• When red light, with its longer wavelength, enters
a glass prism, it slows down the least of all the
colors.
• Red light is ___________ the least.
• Violet light is bent the most.
18.4 Color
Separating White Light Into Colors
The process in which white light separates into
colors is called ______________. A rainbow
forms when droplets of water in the air act like
prisms.
• When light enters a raindrop, it slows down
and refracts. Then it reflects off the far inner
surface of the raindrop.
• It refracts again as it exits the raindrop,
speeds up, and travels back toward the
source of the light.
18.4 Color
The Colors of Objects
What determines the _________ of an
object?
The color of any object depends on what the
object is made of and on the color of
_____________ that strikes the object.
18.4 Color
The Colors of Objects
An object’s color is the color of light that
______________ your __________ when you
look at the object.
• Sunlight contains all the colors of the visible
spectrum.
• A ________ car in sunlight reflects mostly
________ light.
• Most of the rest of the light is
_____________ at the surface of the paint.
18.4 Color
The Colors of Objects
What happens if you change the color of the light
shining on an object?
Only the colors that are in the light can be
________________.
18.4 Color
Mixing Colors of Light
What are the __________ colors of
_________?
Primary colors are three specific colors that
can be combined in varying amounts to create
all ____________ ___________.
The primary colors of light are _______,
_____________, and __________.
18.4 Color
The Colors of Objects
If more than one color of light is reflected from a
surface, the colors of light mix. When colors of
light mix, they add to form a new color.
Each __________________ color of light is a
combination of two primary colors. The secondary
colors of light are ________, ____________, and
________________.
18.4 Color
The Colors of Objects
If you add a primary color to the proper secondary
color, you will get white light.
Two colors of light that combine to form white light
are ________________ colors of light.
A complementary color pair is a combination of
one primary color and one secondary color.
18.4 Color
Mixing Pigments
What are the primary colors of
______________?
The primary colors of pigments are
________, ____________, and
_____________.
18.4 Color
Mixing Pigments
A ________________ is a material that absorbs
some colors of light and reflects other colors.
• Paints, inks, photographs, and dyes get their
colors from pigments.
• Color printers and photocopiers use three
colors–cyan, magenta, and yellow–plus
black.
• You can mix varying amounts of these
primary pigment colors to make almost any
other ___________.
18.4 Color
Mixing Pigments
Each pigment ____________ one or more colors.
As pigments are mixed together, more colors are
________________, and fewer colors are
reflected.
When two or more pigments are mixed together,
the colors absorbed by each pigment are
subtracted out of the light that strikes the mixture.
18.4 Color
Mixing Pigments
Any two colors of pigments that combine to make
_________ pigment are ___________________
colors of pigments.
•
•
•
•
Cyan and magenta combine to form blue.
Cyan and yellow combine to form green.
Yellow and magenta combine to form red.
The _____________ colors of pigments are red,
green, and blue.
18.4 Color
Assessment Questions
1. A prism separates white light into the visible
spectrum because
a. longer wavelengths are absorbed more than shorter
wavelengths.
b. shorter wavelengths refract more than longer
wavelengths.
c. shorter wavelengths reflect more than longer
wavelengths.
d. longer wavelengths experience more interference.
18.4 Color
Assessment Questions
•
The color of an object depends on what the object
is made of and on
•
•
•
•
the intensity of light that strikes the object.
the color of light that strikes the object.
the direction of the light that strikes the object.
the speed of the light that strikes the object.
18.4 Color
Assessment Questions
1. Which of these colors is one of the primary colors
of light?
a.
b.
c.
d.
green
magenta
yellow
white