Light
Chapter 18
Reflection and Mirrors
Opaque - a material that reflects or
absorbs all of the light
Transparent - a material that allows light
to pass through
Translucent - a material that scatters
light as it passes through
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light rays represented in straight lines
regular and diffuse reflection pg.571
image - copy of an object formed by
reflected or refracted rays
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Plane Mirror
produces an image
that is right side up
(virtual) and the
same size as the
object being
reflected
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Concave Mirror
Surface curves
inward.
Forms either a
virtual image or real
image (pg. 573)
– used for make-up
mirrors
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Convex Mirror
Surface curves
outward.
Forms a virtual
image (pg. 574)
– used for security or
blind spots on roads
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Refraction and Lenses
When light rays enter a new medium at
an angle, the change in speed causes
them to bend, or change direction
index of refraction - a measure of how
much a ray of light bends when it enters
that material (pg. 576)
mirage - an image of a distant object
caused by refraction of light
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Concave lenses
parallel light rays
are bent away from
the center of the
lens (pg. 578)
forms virtual image
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Convex lens
parallel light rays
are bent towards the
center of the lens
(pg. 578)
forms virtual or real
image dependent
upon position
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Color
The color of an object is the color of the light
it reflects
primary colors - red, green , blue
when combined the primary colors produce
white light
complementary colors - two colors that
combine to create white light
pigments - substances that are used to color
other materials
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Section 4 - Seeing Light
Eye picture pg.588
– cornea -
– iris -
– pupil -
– lens -
– retina -
– optic nerve -
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nearsighted - eyeball too long.
corrected with concave lens
farsighted - eyeball too short. Corrected
with convex lens
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Section 5 - Using Light
Chapter 18