Confirming Pages
7
Waves
CHAPTER OUTLINE AND GOALS
Your chief goal in reading each section
should be to understand the important
findings and ideas indicated (•) below.
Wave Motion
7.1
•
7.2
•
7.3
•
7.4
•
Water Waves
Crests and Troughs
Waves carry energy but not matter
from one place to another.
Transverse and Longitudinal Waves
Across and Back; Toward and Away
The difference between transverse
and longitudinal waves and how some
waves combine both types.
Describing Waves
Wavelength, Frequency, and Speed
Are Related
The speeds of all waves are related in
the same way to their frequencies and
wavelengths.
Standing Waves
They Generate Most Musical Sounds
The nature of a standing wave and how
it can come into being.
Sound Waves
7.5 Sound
Pressure Waves in a Solid, Liquid, or Gas
• What infrasound, ultrasound, and sonar are.
• How the decibel scale is related to the
energies of sounds.
7.6 Doppler Effect
Higher Pitch When Approaching; Lower
Pitch When Receding
• The origin of the doppler effect.
7.7 Musical Sounds
Fundamentals and Overtones
• How musical sounds are produced.
• What is meant by resonance.
Electromagnetic Waves
7.8 Electromagnetic Waves
Waves Without Matter
• The nature of an elecromagnetic wave.
The dispersion of sunlight by water droplets produces rainbows.
7.9
•
•
7.10
•
Types of EM Waves
They Carry Information as Well as Energy
The difference between amplitude and
frequency modulation of radio signals.
How radar produces an image of its
surroundings.
Light “Rays”
The Paths Light Takes
The ray model of light is a useful simplification in some situations.
Wave Behavior
7.11 Reflection
Mirror, Mirror on the Wall
• How a mirror produces an image of
what is in front of it.
7.12 Refraction
A Change in Direction Caused by a
Change in Speed
• How a wave is refracted at a boundary
between two materials in which its
speed is different.
• Why a body of water seems shallower
than it actually is.
• What is meant by internal reflection
and how it enables a glass fiber to
carry light.
7.13 Lenses
Bending Light to Form an Image
• How light is affected by converging
and diverging lenses.
• The use of ray tracing to find the properties of the image a lens produces.
7.14 The Eye
A Remarkable Optical Instrument
• The structure of the eye.
• The origins of nearsightedness, farsightedness, and astigmatism and how
they can be corrected for.
7.15 Color
Each Frequency of Light Produces the
Sensation of a Different Color
• Why white light is dispersed into a
spectrum when it is refracted.
• How rainbows and the blue color of the
sky come about.
7.16 Interference
Waves in Step and out of Step
• The difference between constructive
and destructive interference.
• Why thin films of oil or soap appear
brightly colored.
7.17 Diffraction
Why Shadows Are Never Completely Dark
• What happens when waves are diffracted at the edge of an obstacle.
• The factors that determine the sharpness of the image produced by an
optical instrument.
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