Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
46 Cards in this Set
- Front
- Back
|
Definition of Sound
|
mechanical, longitudinal wave that travels in a straight line
|
|
|
A sound wave is made up of what two things?
|
compression and rarefaction
|
|
|
Define Period and state unit
|
length of time it takes to complete a single cycle
seconds |
|
|
What parameters can be changed by the sonographer?
|
Amplitude, power and intensity
|
|
|
What parameters are determined by the sound source only?
|
Period, Frequency, amplitude, power, and intensity.
|
|
|
What parameter are determined by both sound source and medium?
|
wavelength
|
|
|
What parameter is determined by the medium only?
|
propagation speed
|
|
|
Define propagation speed and state unit
|
speed at which sound moves through a medium
m/second |
|
|
State the relationship between speed and density, and speed and stiffness.
|
if density increases, speed decreases
if stiffness increases, speed increases |
|
|
Put the following things in order of speed from slowest to fastest...
liquid, solid, gas |
gas, liquid, solid
|
|
|
Put in order the following things in order of slowest to fastest..brain, kidney, liver, air, soft tissue, and muscle.
|
air, brain, soft tissue, liver, kidney, muscle
|
|
|
What is the speed of sound through soft tissue?
|
1540m/s or
1.54 km/s or 1.54 mm/us |
|
|
define mathematically propagation speed.
|
propagation speed= frequency (Hz)* wavelength (m)
|
|
|
Define Frequency and state unit
|
the # of certain events that occur in a specific duration of time
1/sec or Hertz |
|
|
Define the ranges for infrasound, audible sound and ultrasound.
|
Infrasound= <20 Hz
audible sound=20Hz-20kHz ultrasound= >20kHz |
|
|
what is the clinical imaging range for period?
|
.1 to .5us
|
|
|
What is the clinical imaging range for frequency?
|
2MHz to 10MHz
|
|
|
What is the clinical imaging range for amplitude?
|
1MPa to 3MPa
|
|
|
What is the clinical imaging range for Power?
|
4-90mW
|
|
|
What is the clinical imaging range for intensity?
|
.01-300 W/cm^2
|
|
|
What is the clinical imaging range for Wavelength?
|
.1-.8mm
|
|
|
What is the clinical imaging range for propagation speed?
|
500 m/s to 4000 m/s
|
|
|
State the relationship between period and frequency, and wavelength and frequency?
|
They are inverse of each other
|
|
|
Can you change frequency without changing period?
|
no, frequency is determined by period.
|
|
|
Define amplitude and state its unit of measure
|
the strength of a wave-the magnitude of the wave
any units of acoustic variable, degrees, cm, grams/cubic cm, Pascals, decibels |
|
|
Define power and state the unit of measure
|
relates to strength,
it is the rate in which work is performed or energy is transferred from the entire sound beam units: watts |
|
|
state the relationship between power and amplitude
|
directly related, power=amplitude squared
|
|
|
state the relationship between intensity and amplitude
|
directly related, intensity=amplitude squared
|
|
|
Define intensity and state the unit of measure
|
relates to the strength of a sound beam, it is the concentration of energy in a sound beam
watts/cm ^2 |
|
|
Define intensity mathematically
|
intensity= power of a beam/ its cross sectional area
|
|
|
Define wavelength and state unit of measure
|
distance of length that one cycle occupies
mm, cm, or meter |
|
|
define wavelength mathematically
|
wavelength= propagation speed(mm/us) / frequency (MHz)
|
|
|
which image would have better quality and longitudinal resolution?
A-high frequency, short wavelength B-Low frequency, long wavelength |
image A
|
|
|
If frequency increases what does period do?
|
decrease
|
|
|
What does amplitude, power and intensity do as sound propagates through the body?
|
they decrease
|
|
|
If amplitude is increased 3x than what does power do?
|
it is increased 9x
|
|
|
if amplitude is increased 3x than what does intensity do?
|
it is increased 9x
|
|
|
if power is doubled than what does intensity do?
|
it is doubled
|
|
|
If wavelength increases what does frequency do?
|
it decreases
|
|
|
What is density?
|
concentration of mass per unit of volume
|
|
|
What is stiffness?
|
materials ability to maintain it's shape
|
|
|
If density increases what does speed do?
|
it decreases
|
|
|
If stiffness increases what does speed do?
|
it increases
|
|
|
convert 3 seconds to million seconds and then to micro seconds
|
3 seconds= .000003 Ms or
3*10^6 seconds 3 secs= 3000000 us or 3*10^-6 seconds |
|
|
name two complimentary unit relations
|
giga and nano (billion & billionths, 10^9 & 10-9)
mega and micro (million & millionths, 10^6 & 10^-6) |
|
|
State the following units power of 10
giga, mega, kilo, hecto, deca, deci, centi, milli, ,micro, nano |
10^9 giga
10^6 mega 10^3 kilo 10^2 hecto 10^1 deca 10^-1 deci 10^-2 centi 10^-3 milli 10^-6 micro 10^-9 nano |
