Chapter 2 Terms/ Relationships
What does media/medium mean?
Tissue
Sound travels___
in a straight line
Sound waves are____waves.
longitudinal
All sound waves carry___from one place to another.
energy
Sound is a type of___ wave.
mechanical
Particles in a mechanical wave____ back and forth.
vibrate
Sound___ travel through a vacuum. It ____ move through a medium where the molecules are constantly squeezed.
cannot; must
What is it called when molecules are constantly squeezed?
compressed waves
What does it mean when molecules are constantly stretched?
rarefied waves
What is increased pressure and density?
compressions
What is decreased pressure and density?
rarefactions
What identify which waves are sound waves?
Acoustic Variables
How do we know we are dealing eith sound waves?
Based on oscillations or rhythmical changes in time in acoustic variables
What does it mean when acoustic variables have a rhythmic oscillation?
It is a sound wave
If something other than pressure, density, or distance/motion rhythmically oscillates in the wave, it is _______
not a sound wave
What are the acoustic variables?
Pressure, Density, and Distance
What is pressure?
Concentration of force in an area
What are units of pressure?
Pascals (Pa)
What is the equation for pressure?
Force/area
What is density?
Concentration of mass in a volume
What are the units of density?
kg/cm cubed
What is distance?
Measure of particle motion
What are the units of distance?
cm, feet, mile
What are transverse waves?
When particles are moving perpendicular to the direction that the wave propagates
When you hold a string and shake it up and down, what does this create?
A transverse wave
When you hold a string and shake it up and down, the energy from the oscillations move in a ______ direction and ____ from your hand.
perpendicular; away
What are longitudinal waves?
When particles move in the same direction that the wave propagates
Sound is a____wave.
Longitudinal
A longitudinal wave moves ____ to _____ and _____ to _____, and they ___ along as they travel.
left; right; right; left; wiggle
What are acoustic parameters?
Characteristics of a sound wave
What do acoustic parameters do?
Describe the sound wave
How manh acoustic parameters are there?
7
An ______ wave is when a pair of waves have their peaks occur at the same time and same location, and same with their minimum waves.
in phase
An _____ wave is when 2 waves have peaks at different times, and same with their minimum waves.
out of phase
What is it when you have more than one sound beam traveling in a medium and they arrive at the same location at the same time?
Interference
What is it called when in phase waves interfere?
Constructive Interference
What is it called when out of phase waves interfere?
Destructive Interference
When there is one wave that has a lesser amplitude that its components it is called_____.
destructive interference
When there is a single wave of greater amplitude than either smaller wave, it is called_____.
constructive interference
What is the effects of the sound wave upon the biologic tissue through which it passes?
Biologic effects