Ch 2: Sound Flashcards
acoustic propagation properties
the effects of the medium upon the sound wave
biologic effects
the effects of the sound wave upon the biologic tissue through which it passes
compressed
squeezed together
rarefied
stretched apart
Sound travels in a (straight/crooked) line.
straight
Sound waves are (longitudinal/transverse) waves.
longitudinal
These are used to distinguish between sound waves and other types of waves.
acoustic variables
Name the acoustic variables.
pressure, density, distance
Define pressure
concentration of force in an area - units: pascals (Pa)
Define density
concentration of mass in a volume - units: kg/cm^3
Define distance
measure of particle motion - units: cm, mm
These are required to completely describe the features of a sound wave.
acoustic parameters
Name the acoustic parameters.
period, frequency, amplitude, power, intensity, wavelength, propagation speed
transverse wave
wave in which the particles move in a direction that is perpendicular to the direction fo the wave.
longitudinal wave
wave in which the particles move in the same direction of the wave.
in-phase
when the peaks and troughs of a pair of waves occur at the same time and place
out-of-phase
when the peaks and troughs of a pair of waves occur at a different time and place
interference
when a wave combines with another wave and loses its individual characteristics
constructive interference
when a pair of in-phase waves combine to form a greater amplitude than either of its components
destructive interference
when a pair of out-of-phase waves combine to form a lesser amplitude of its components
Both constructive and destructive interference occurs when…
two waves of differing frequencies combine.
