Download Mr. Hartman/Ms. Slack Date:______ Chapter 19

Name:______________________________________
Mr. Hartman/Ms. Slack
Period:_______
Date:________
Chapter 19 – Section 3
Refraction and Lenses
Pages 562 - 566
Bending of Light Rays
Objects in ____________ can sometimes look strange.
A pencil in a glass of water sometimes looks as if it _________ or ____________.
Illusions such as these are due to _________________________ as they pass from
one material to another.
The Speeds of Light
The speed of light in empty space is about ______________________.
Light passing through a medium such as air, water, or glass, however, travels ________
_____________ than this.
This is because the atoms that make up the material interact with the light waves and
_________________________.
The Refraction of Light Waves
If a light wave travels from one medium to another, the light wave will ____________.
This can cause light to _____________________ or _____________.
The bending of light waves due to a change in speed is called ___________________.
Convex and Concave Lenses
Taking photographs of friends or looking through a magnifying glass involves the use of
a ________.
A lens is a transparent object with at least _____________________ that causes
light to bend.
The more curved the sides of the lens are, the more light will be ______ after it
enters the lens.
Convex Lenses
A lens that is thicker in the center than at the edges is a ____________.
Because convex lenses cause light waves to meet, they are also called
_________________________.
The more curved the lens is, the closer the focal point is to the lens,
and so the shorter the ________________.
If the object is two focal lengths from the lens, the image seen through
the lens is ____________ and _________________ than the object.
If the object is closer to the lens than one focal length, then the image formed is
_________________ and ________________ than the object.
A __________________________ forms an image this way.
Concave Lenses
A lens that is thicker in the edges than in the middle is a _____________.
A concave lens is also called a ___________________.
A concave lens causes light rays to diverge so there is ________________.
The image formed by a concave lens is similar to
that of a ____________________.
The image is ____________ and ____________ than the object.
Total Internal Reflection
When you look at a glass window, you can sometimes see your reflection..this is an
example of ______________________.
However, sometimes all the light waves that strike a boundary between two transparent
materials can be reflected…this process is called _________________.
The Critical Angle
If a light beam in water strikes the air-water boundary at an angle greater than the
_______________________, total internal reflection occurs.
When this happens all the light waves are reflected just as if a __________ was there.
The size of the critical angle depends on the __________________ involved….for airwater the critical angle is _____________.
Optical Fibers
Optical fibers are thin, flexible, ______________________ that act like a light pipe.
Total internal reflection makes _______________________ in optical fibers possible.
Optical fibers are used for sending light signals used in:
________________________________________________.