Registry review 1 Flashcards
______________ the effects of the medium upon the sound wave
Acoustic Propagation Properties
Wavelength
Frequency
Bandwidth
Acoustic Propagation Properties
What is the units for Amplitude? May be more that one.
Mhz
Tesla
Pascals
dB
distance
dB
Pascals
_________ The time required to complete a single cycle.
Wavelength
Frequency
Period
Amplitude
Period
__________ is the distance covered by one cycle
pulse length
wavelength
cycle distance
cycle duration
wavelength
___________ is the time to complete one cycle
pulse duration
pulse period
period
duration period
period
____________ are regions of higher density and pressure
Rarefractions
Compressions
Period
Acoustic variables
Compressions
A pulse collection of cycles that travel together are called pulsed sound
True
False
True
A wave with a frequency of 15,000 Mhz is ultrasonic? Watch your units..
True
False
True
All but one are acoustic parameters. Which one is not a parameter
period
frequency
amplitude
Power
Intensity
speed
wavelength
Pulse Repetition Frequency
Pulse Repetition Frequency
As a result of ___________ the propagation speed increases
increasing stiffness and increasing density
increasing stiffness and increaing elasticity
decreasing compressiblity and decreasing density
decreasing stiffness and decreasing density
decreasing compressiblity and decreasing density
As sound propagates through the body. What happens to the power
increases
decreases
decreases
Compressibility and Elasticity are the same as stiffness?
True
False
False
How are frequency and period related? If you increase frequency what happens to period
increases
decreases
decreases
How are Frequency and Wavelength related? If you increase you frequency what happens to wavelength
decreases
increases
doubles
quarters
decreases
If the frequency of US is increased from .77 Mhz to 1.54Mhz, what happens to the wavelength?
doubles
halves
remains same
4 times greater
halves
If you increase stiffness the speed will decrease?
True
False
False
Number of certain events that occur in a particular time duration.
wavelength
period
frequency
amplitude
frequency
Occurs when the amplitude of the new, combined wave is greater than the original two waves. In-phase waves interfere____________
constructive Interference
Destructive Interference
constructive Interference
Particles move in a perpendicular direction ( right angles or 90 degree to the direction of the wave:
longitudinal wave
transverse wave
Horizontal wave
Tidal wave
transverse wave
Propagation speed + _________x wavelength
pulse duration
period
number of cycles in the pulse
frequency
frequency
Pulse repetition period is the time from the start of one pulse to the start of the next pulse?
PRP pulse rep period
PRF pulse rep freq
Pulse duration
Spatial pulse length
PRP pulse rep period
Put these typical values in order from slow to fast according to there propagation speed. tendon, bone, air, fat, soft tissue, lung
Air, lung, fat, soft tissue, tendon, bone
Air, lung, fat, soft tissue, tendon, bone
Sound is a transverse, mechanical wave?
True
False
False
Sound waves are
electric
mechanical, transverse
spectral
longitudinal, mechanical
longitudinal, mechanical
The difference between the average value and the maximum value of an acoustic variable. The variation of an acoustic variable.
Amplitude
Frequency
Power
Intensity
Amplitude
The rate that sound travels through a medium. Also called velocity or speed.
Propagation speed
power
amplitude
intensity
Propagation speed
What is the Frequency of US
19,000 khz
10,000 Mhz
20,000 msec
20,000 Hz
20,000 Hz
T or F: The power Doppler evaulates speed and direction.
T
F
F
How many PZT crystals does a PW transducer have?
1
2
3
4
1
The time from START of a pulse to the END of that pulse, the actual time the pulse is on
Pulse Duration
Pulse Repetition period
Pulse Repetition Frequency
Pulse
Pulse Duration
T or F: Undampened transmitted signal, narrow bandwidth, high quality factor, and higher sensitivity are related to cw transducers
T
F
T
The percentage or fraction of time that the system transmits sound. Important when discussing intensities.
Duty Factor
Period
PRP
PRF
Duty Factor
T or F: the sonographer positions a small marker called sample volume, or gate while in CW mode
T
F
No answer text provided.
F
Does CW transducers have backing material
no
yes
no
What effects penetration and axial resolution (image quality)
Frequency
Amplitude
Period
Wavelength
Frequency
Which transducer has the ability to select the exact location where velocities are measured?
pw
cw
pw
which of the following is determined by the source and the medium?
frequency
period
propagation speed
range resolution
range resolution
What is the relationship of power and amplitude? If the amplitude is doubled, the power is ______
Quadrupled
Halved
Quartered
doubled
Quadrupled
This is the equation for? __________ watts/cm2 = power/beam area cm2
Intensity
Wavelength
Power
Frequency
Intensity
A false identity is describing?
aliasing
shadowing
speckle
aliasing
What is the main advantage the CW has over the PW?
range resolution
anatomical imaging
measure high velocities
non directional or speed
measure high velocities
All except one are ways to reduce aliasing in pw
adjust scale to minimum
select a new view
selec a lower freq
us cw
adjust scale to minimum
When two waves overlap at the same location and at the same instant in time, they combine into one new wave.
Interference
frequency
Phase
Annoying
Interference
Which is not an acoustic variable
density
pressure
distance
intensity
intensity
The nyquist is ___ of the pulse repetition freq.
double
one half
quadrupled
1/4
one half
Flow towards the transducer will display the velocities?
above baseline
below baseline
not at all
above baseline
A disadvantage of ____ is inaccurate measurement of high velocities.
pw
cw
pw
The number of pulses that occur in one second.
pulse rep period
pulse rep frequency
duty factor
Q factor
pulse rep frequency
Color maps uses a dictionary, or lookup table, to convert measured _____into colors that appear on the image.
frequency
velocities
pressures
energies
velocities
T or F: Aliasing is only created in CW Doppler
T
F
F
What is the most common error assoc with Doppler US
shadowing
burst artifact
splash aritfact
aliasing
aliasing
Which of the below transducers emits a sound pulse and then waits that time of flight before briefly listening for a reflection.
PW
CW
PW
Velocity information is coded into colors and superimposed on a two-dimensional gray scale, anatomic image describes what?
Color Doppler
pwdoppler
frequency
cw
Color Doppler
The two components of pulsed ultrasound are 1. the cycles( on or transmit time) and 2. the dead time ( off time or receive time)
True
False
True
The effects of soft tissue on US are called
acoustic proliferation properties
dynamic propagation
acoustic propagation properties
Biologic effects
acoustic propagation properties
High velocity flow in one direction is incorrectly displayed as traveling in the opposite direction.
range ambiguity
range resolution
aliasing
aliasing
T or F: the dictionaries are called velocity mode and variance mode.
T
F
T
What is the units for Wavelength
Correct!
meters, mm or any unit of length
dB
watts
14,000 Gigawatts
meters, mm or any unit of length
The time from the beginning of a pulse until its end is___________?
period
pulse duration
pulse length
PRF
pulse duration
Which of the below reports average or mean vleocities?
pw
cw
color doppler
color doppler
What is the pairing that belongs to the prefix giga?
nano
mega
deca
deci
nano
The rate at work is performed, or the rate of energy transfer
Intensity
Power
Amplitude
Voltage
Power
The very top of the display is called the ______ and the part of the spectrum appearing at the bottom is called aliasing
speed limit
nyquist limit
nyquil night time
No answer text provided.
nyquist limit
Can a dedicated cw transducer create an anatomical image
yes
no
no
How many crystals does the CW transducer use
1
2
3
4
2
The length or distance that an entire pulse occupies in space. The distance from the start to the end of one pulse is spatial pulse length?
True
False
True
The speed closest to US in soft tissue
1,540 km/sec
1.54 km/msec
1,500 m/s
1,540 mm/sec
1,500 m/s
Which mode provide info on flow direction and velocity only
velocity mode
variance mode
velocity mode
What can we do to get rid of aliasing?
raise baseline
lower freq transducer
change patients
lower freq transducer
The crystal alternates between sending and receiving sound pulses. This describes which transducer
PW
CW
MW
A&W
PW
What is the limitation of CW?
range resolution
range ambiguity
range ambiguity
Wide of the below has a wide bandwidth?
pw
cw
pw
In PW the US system then calculates the ___________ for a sound pulse traveling to a form the gate.
frequency
period
time of flight
time of day
time of flight
What happens to the color scanning at a 90 degree angle in color doppler
red
blue
black
nothing
black
