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5 5 Wave Motions
and Sound
Compared to the sounds you hear on a calm day in the woods, the sounds
from a waterfall can carry up to a million times more energy.
CORE CONCEPT
Sound is transmitted as increased and decreased pressure waves that carry energy.
OUTLINE
5.1 Forces and Elastic Materials
Forces and Vibrations
Describing Vibrations
Waves
5.2 Waves
Mechanical waves are Kinds of Mechanical Waves
longitudinal or transverse. Waves in Air
5.3 Describing Waves Sound Waves
5.4 Sound Waves
Sound Waves in Air and Hearing All sounds traveling through
Medium Required air are longitudinal waves that
A Closer Look: Hearing Problems originate from vibrating matter.
Velocity of Sound in Air
Refraction and Reflection
Refraction
Reflection
How Loud Is That Sound? Interference Resonance
The loudness of a sound is Constructive and Destructive An external force with a
related to the intensity of a Beats frequency that matches the
sound wave, which can be 5.5 Energy of Waves natural frequency of an object
measured on the decibel scale. How Loud Is That Sound? results in resonance.
Resonance
5.6 Sources of Sounds
Vibrating Strings
Vibrating Strings
Science and Society: Laser Bug Sounds from Moving Sources
A recognizable musical note
Sounds from Moving Sources The Doppler effect is an apparent
from an instrument is from a People Behind the Science:
combination of fundamental and Johann Christian Doppler change of pitch brought about
overtone frequencies produced A Closer Look: Doppler Radar by the relative motion between a
sound source and a receiver.
by that instrument.
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