# Phys ch 19-21

## Terms

copy deck
Energy can be transferred from a source to a reciever without the transfer of matter between two points
Wave motion
High points of a sine wave
Crests
The low points of a sine wave
Troughs
The distance from the top of one crest to the top of the next one.
Wavelegnth
Related to the frequency and wavelegnth of the waves.
Wave speed
wvlgth x freq
How frequently a vibration occurs
frequency
The time for one complete vibration
Period
The distance from the midpoint to the crest or trough of the wave
Amplitude
Right-angled, sideways motion. The motion is transverse to the direction the wave travels.
Transverse wave
Parts that make up a medium move to and fro in the same direction in which the wave travels. Motion along the direction of the wave, not at right angles
Longitudinal wave
When one the crest of one wave overlaps the crest of another, their individual effects add together to produce a wave of increased amplitude
Consturctive interference
When the crest of one wave overlaps the trough of another, their individual effects are reduced.
Destructive interference
A wave in which parts of the wave, called nodes, are stationary
Standing wave
Give 3 examples of everyday longitudinal and trasverse waves
T-
An echo
Reflection
Must be present for sound to travel through
medium
A pulse of compressed air
Compression
Travels at 340 m/s
Speed of sound in air
The _____ of a sound relates to its frequency
Pitch
High frequency produces a _____ note, and low frequency produces a ____ note
High/low
Depends on the amplitude of pressure variations within the sound wave.
Intensity
A physiological sensation
Loudness
Phenomenon that occurs when the frequency of forced vibrations on an object matches the object's natural frequency,producing a dramatic increase in amplitude
Resonance
Chnage in frequency of a wave of sound or light due to the motion of the source or the reciever.
Doppler effect

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