Chapter 1-3 Flashcards
unrelated
two item not associate
related or proportional
two item associated or affiliated
directly related / proportional
1 ⬆️, 1 ⬆️
inversely related / proportional
1 ⬆️, 1 ⬇️
reciprocal
two number w/ reciprocal relational are multipled tg = 1
what kind of relation is reciprocal ?
inverse relationship 1 ⬆️, 1 ⬇️
units : length
distance or circumference : cm, feet
units : area
cm2 , ft2
units : volume
cm3, ft3
in scientific notation form w/ positive exponent has a value …..
greater than 10
in scientific notation form w/ negative exponent has a value …..
less than 1
in scientific notation form w/ exponent : zero has a value …..
b/w 1-10
sound is …. wave
Mechanical
sound can not travel through …
it must travel through
vacuum
medium
molecules are alternately ….
compressed / rarefied
sound travels in a …. line
straight
sound was are …. waves
longitudinal
acoustic propagation properties
effects : medium upon sound wave
biologic effect
effect : sound wave upon biological tissue through which is passing
what are used to distinguish b/w sound wave / other time of waves
3 acoustic variable
- pressure
- density
- distance
pressure
concentration : force in an area
units : pressure
pascals (Pa)
density
concentration : mass in volume
unit : density
kg/cm3
distance
measure : particle motion
units : distance
cm,feet,mile
what is used to describe wave feature ?
7 acoustic parameters
- period
- frequency
- amplitude
- power
- intensity
- wavelength
- Propagation speed
transverse wave
particles move in direction > perpendicular ( at right angles) to direction > wave propagates
Longitudinal wave
particles moves > same direction > wave propagates
sound is ….. wave
Longitudinal
In - phase wave
peak ( max value) occurs at the same time / location
out - phase wave
peak occurs at different time
interface
- more than one sound beam may travel > medium
- multiple beam may arrive at identical location at exactly same time
- wave lose individual characteristic, combines to form a single wave
constructive interference
interference : in-phase wave = forming : single wave : greater amplitude than either : it component
- resulting wave > larger than component
destructive interface
interference : out : phase wave = forming : single wave : lesser amplitude that at least one : its component
-resulting wave > smaller than 1 : it component
complete destructive interference
two out-phase wave are equal amplitude
source : sound wave
ultrasound system / transducer
another word > medium
tissue
period
time it take wave to vibrate a single cycle
OR
time from start : 1 cycle to start : next cycle
units : period
time
Microseconds (us)
seconds
hours
days
period determined by
sound source only
can period be adjusted
No
frequency
: particular events that occur > specific duration : time
frequency : wave describes
: cycles > occurs > 1 seconds
units : frequency
per second
1/second
hertz (Hz)
kHz
MHz
frequency determined by
sound source only
can frequency be adjusted
No
frequency : sound wave > less than 20 Hz
- below human hearing / cannot be heard
Infrasonic / infrasound
human can hear sound w/ frequencies b/w 20-20,000 Hz
audible
sound w/ frequencies so high human can not hear
ultrasonic / ultrasound
ultrasound frequency is higher than …..
20,000 Hz ( 20 kHz)
frequency affects …
penetration / image quality
period / frequency ….. related
inversely
Frequency ⬆️, period ⬇️
Frequency ⬇️, period ⬆️
period / frequency special relationships
reciprocal
period x frequency = 1
hertz
events per second
what is the meaning of: sound wave w/ frequency : 100 Hz
- 100 event occurs each seconds
- cycle is our event.
100 Hz = 100 cycles per second
what is the meaning of an individual’s / heart rate : 1 Hz
- 1 event occur each second
2.heartbeat is the event
Individuals earn contracts at rate : 1 beat per second ( 60 beats per min)
3 parameters describe size, magnitude, strength : sound wave
- amplitude
2.power
3.intensity
amplitude
“bigness” : waves
- difference between/w max value / average or undisturbed value : acoustic variable
- difference b/w mini value / average value : acoustic variable
units : amplitude
pressure - pascals
density - g/cm3
particle motion - clinches, any distance
decibels - dB
amplitude determined by
sound source only
amplitude ….. as sound propagates through body
⬇️
can amplitude be adjustable
Yes
amplitude is measured
from middle, undisturbed value to maxi value
peak - peak amplitude
difference b/w max / min value : acoustic variable
peak - peak amplitude > …. value : amplitude
twice
power
rate : energy transfer
OR
rate at which work is performed
units : power
watts
power determined by
sound source only
can power be adjustable
Yes
amplitude / power
parameter that describes size or magnitude : wave
amplitude / power … related
directly
amplitude ⬆️, power ⬆️
amplitude ⬇️, power ⬆️
intensity
concentration : energy in sound beam
how you calculate intensity
divide beam power by beam cross - sectional area
Intensity relates to
how power in wave spreads or disturbed in space
intensity depends on
both power on beam / area over which power is applied
units : intensity
watts / square cm ( W/cm2)
- watts = power
- cm2 = beam area
intensity (W/cm2) =10,000 kg/sec³ power (w) / area cm2)
intensity determined by
sound source only
can intensity be adjusted
Yes
Amplitude, power, intensity …… related
directly
1 ⬆️, 1 ⬆️
intensity / power ….. Relationships
Proportional ♾️
intensity … to wave …….
proportional / amplitude squared
♾️
squared means
multiple by itself
wavelength
distance or length : 1 complete cycle
units : wavelength
mm
meters
any units : length
wavelength determined by
both source / medium
can wavelength be adjusted
NO
wavelength / frequency ….. related
Inversely
frequency ⬆️, wavelength ⬇️
what is the only parameter that is determined both source / medium
wavelength
the lower ….. , longer …..
frequency, wavelength
how do you find wavelength : sound wave > soft tissue
divide 1.54 mm by frequency in MHz
wavelength ( mm) = 1.54mm/us/ frequency (MHz)
wavelength affects ….
image quality
shorter wavelength created by …… & produces …..
high frequency sound & higher quality image w/ greater detail
sonographer should use ….. frequency transducer rather than …….. frequency transducer
higher / lower
propagation speed
rate at which sound wave travels through a medium
units : propagation speed
meters per seconds
mm
us
any distance divided by time
propagation speed determined by
only by medium in which sound is traveling
can propagation speed be adjusted
NO
what is the average or typical biological medium ?
soft tissue
what is the speed : sound > soft tissue
1,540 m/s
1.54 mm/us OR km/s ( 1 mile per sec)
2 characteristic : medium affect speed : sound
- stiffness
- density
stiffness
Ability : object to resist compression
stiffness / speed …… related
Directly
1 ⬆️, 1 ⬆️
as material become stiffer, speed : sound > material ….
⬆️
another name for stiffness
bulk modulus
what is the opposite of stiffness
elasticity & compressibility
density
weight of material
density / speed … related
inversely
1 ⬆️, 1 ⬇️
material become more dense ( heavier), speed : sound > material …..
decrease
sound travels …. in media w/ low density
faster
speed is determined by …. & ….. : medium
density & stiffness
material > stiff but no dense will have …. speed
faster
material > not stiff & very dense will have …. speed
slowest
5 parameter determined by sound source only
- period
- frequency
- amplitude
- power
- intensity
period / frequency …. relationship
Reciprocal
3 parameters that describe the magnitude : sound wave
( BIG 3 )
- amplitude
- power
- Intensity
what are the only 3 parameter that sonographer can adjust
- amplitude
- power
- Intensity
what is the only parameter determined by both sound source & medium
wavelength
what the only parameter determined solely by medium through which it sound travels
speed
