Ch. 2 Sound Flashcards
All waves carry _______ from one location to another.
All waves carry energy from one location to another
Sound is a ___________________ wave, in which particles in the medium move
Sound is a mechanical wave, in which particles in the medium move
Sound cannot travel though a ________________________, it must travel through a medium
Sound cannot travel through a vacuum it must travel through a medium
When sound travels through a medium, molecules are alternately _______________________ and ____________________
When sound travels through a medium, molecules are alternately compressed (squeezed together) and rarefied ( stretched apart)
Sound travels in a ________________ line
Sound travels in a straight line
Sound waves are _______________________ waves
Sound waves are longitudinal waves
______________ ______________________ ________________ are the effects of the medium upon the sound wave
acoustic propagation properties are the effects of the medium upon the sound wave
__________________ effects are the effects of the sound wave upon the biologic tissue through which it passes
Biologic effects are the effects of the sound wave upon the biologic tissue through which it passes
What are the 3 acoustic variables?
- Pressure
- Density
- Distance
_____________________ is the concentration of force in an area
pressure is the concentration of force in an area
___________________ is concentration of mass in a volume
density is concentration of mass in a volume
______________________ is the measure of particle motion
distance is the measure of particle motion
What are the units of pressure?
Pascals (Pa)
What are the units of density?
kg/mL and kg/cm^3
What are the units of distance?
cm, feet, mile, mm, etc.
Sound waves are also known as _______________________ waves
Sound waves are also known as acoustic waves
What are the 7 acoustic parameters?
- Period
- Frequency
- Amplitude
- Power
- Intensity
- Wavelength
- Propagation speed
In a ______________________wave, particles move in a direction that is perpendicular to the direction that the wave propagates
In a transverse wave particles move in a direction that is perpendicular to the direction that the wave propagates
In a ___________________________ wave particles move in the same direction that the wave propagates
In a longitudinal wave particles move in the same direction that the wave propagates
A pair of waves are considered _________________ when their peaks (maximum values) occur at the same time and at the same location.
A pair of waves are considered in-phase when their peaks (maximum values) occur at the same time and at the same location
When two waves are _______________________ their peaks occur at different times, and so do their troughs.
When two waves are out-of-phase their peaks occur at different times, and so do their troughs.
When on occasion, multiple beams arrive in an identical location at the same time the waves loose their individual characteristics and form a single wave: this combination is called ______________________________
When on occasion, multiple beams arrive in an identical location at the same time the waves loose their individual characteristics and form a single wave: this combination is called Interference
Both in-phase and out-of-phase wave pairs undergo ______.
interference; however they combine differently
A pair of in-phase waves results in the formation of a single wave of greater amplitude than either of its components. This combination is called ________________________ interference.
A pair of in-phase waves results in the formation of a single wave of greater amplitude than either of its components. This combination is called constructive interference
______________________ interference is where the resulting wave is larger than either of its components
constructive interference is where the resulting wave is larger than either of its components
A pair of out-of-phase waves results in the formation of a single wave of lesser amplitude than at least one of its components. This combination is called _________________________ interference.
A pair of out-of-phase waves results in the formation of a single wave of lesser amplitude than at least one of its components. This combination is called destructive interference
__________________________ interference is where the resultant wave is smaller than one of its components
destructive interference is where the resultant wave is smaller than one of its components
When two out-of-phase waves are of equal amplitude, _______________________ _______________________ interference may occur
When two out-of-phase waves are of equal amplitude, complete destructive interference may occur
What do waves transfer from one location to another?
A. matter
B. molecules
C. energy
D. water
C. waves carry energy from place to place
Which of the following best describes sound waves?
A. a series of compression’s and rarefractions
B. waves that are heard by man
C. movement of molecules and energy from one location to another
D. waves that are used to make images of anatomy
A. sound waves are a series of compressions and rarefactions
Which of the following terms does not belong with the others?
A. compression
B. region of high density
C. region of high pressure
D. wide molecular spacing
D does not belong
Variations in all of the following identify specific waves as acoustic waves except:
A. pressure
B. parameters
C. density
D. acoustic variables
B parameters
All of the following are true of sound waves except:
A. they are acoustic
B. they are pressure waves
C. they are transverse
D. they move energy
C. sound waves are longitudinal, not transverse
All of the following are acoustic parameters except:
A. pressure
B. period
C. propagation speed
D. frequency
A. pressure is an acoustic variable, not a parameter
Which of the following best describes sound waves?
A. transverse, pressure waves
B. transverse, longitudinal waves
C. longitudinal waves, out-of-phase waves
D. longitudinal, pressure waves
D. longitudinal, pressure waves best describe sound waves
Two waves are traveling in a medium and arrive at a location at the same time. What event takes place?
A. constructive interference
B. destructive interference
C. interference
D. reflection
C. When two waves are traveling in a medium and arrive at a location at the same time. Interference takes place
Which types of waves will exhibit both constructive and destructive interference?
A. waves of different amplitude
B. a pair of longitudinal waves
C. waves of different frequency
D. out-of-phase waves
C. both constructive and deconstruction interference occurs with waves with different frequencies
What units are used to report the pressure of a sound beam?
A. pounds
B. centimeters
C. pascals
D. kg/cm
C. pressure is appropriately reported with units of pascals, abbreviated Pa
True or False? Acoustic variables allow us to determine which waves are sound waves and which are not.
True
True or False? Acoustic parameters are used to describe the features of sound waves
True
