Frage 1
Frage
The frequency of a transducer does not change. If the diameter of the new piezoelectric crystal increase, what happens happens to the near zone length?
Antworten
-
increases
-
decreases
-
no change
Frage 2
Frage
The frequency of a transducer does not change. If the diameter of the new piezoelectric crystal increases, what happens to the beam diameter in the far zone?
Antworten
-
increases
-
decreases
-
no change
Frage 3
Frage
The frequency of a transducer does not change. If the diameter of the new piezoelectric crystals increases, what happens to wavelength?
Antworten
-
increases
-
decreases
-
no change
Frage 4
Frage
The frequency of a transducer does not change. If the diameter of the new piezoelectric crystal increase, what happens to the beam diameter in the near zone?
Antworten
-
increases
-
decreases
-
no change
Frage 5
Frage
At the location is the sound beam diameter three time greater than the transducer diameter?
Antworten
-
at the end of the near zone
-
at the depth equal to four focal lengths
-
at the end of the far zone
-
at the triple-diameter depth
Frage 6
Frage
What is the shape of a sound beam created by a tiny piece of PZT?
Antworten
-
hourglass shaped
-
V-shaped
-
round
-
shaped like a tube
Frage 7
Frage
Which of the following explains why a sound beam created by a disc-shaped crystal is hourglass-shaped?
Antworten
-
Bernoulli's Principle
-
Sheffield's Law
-
Ohm's Law
-
Huygen's Principle
Frage 8
Frage
Which of the following locations is the deepest?
Frage 9
Frage
Which of the following locations is the most shallow?
Antworten
-
beginning of the far zone
-
beginning of the focal zone
-
focal depth
-
beginning of the Fraunhofer zone
Frage 10
Frage
A pair of 6MHz probes are identical excepts for the active element diameter. The active element diameters are 6mm and 10mm. The sound beam of which probe will have a shallower focus?
Frage 11
Frage
A pair of 9mm diameter probes are identical except for frequency, which is 3MHZ and 6MHz. WHich beam will have shallower focus?
Frage 12
Frage
Which of the following probes creates a beam with the deepest focus?
Antworten
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8MHz
Frage 13
Frage
Which of the following probes creates a beam with the shallowest focus?
Antworten
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8MHz
Frage 14
Frage
Which of the following probes creates a beam with a the shallowest focus?
Antworten
-
small diameter, high frequency
-
large diameter, high frequency
-
small diameter, low frequency
-
large diameter, low frequency
Frage 15
Frage
Active elements diameter and near zone are directly related?
Frage 16
Frage
Transducer frequency and near zone length are inversely related.
Frage 17
Frage
Wavelength and near zone length are inversely related.
Frage 18
Frage
A pair of 6 MHz probes are identical excepts for the active element diameter, which is 6 mm and 10 mm. Which beam will be more compact in the far field?
Frage 19
Frage
A pair of 9 mm diameter probes are identical except for frequncies, which are 3 MHz and 6MHz. Which sound beam will spread out more in the far field>
Frage 20
Frage
Which of the following probes creates a beam with least divergence?
Antworten
-
4 mm diameter, 4MHz
-
6 mm diameter, 8MHz
-
6 mm diameter, 2MHz
-
5 mm diameter, 8 MHz
Frage 21
Frage
Which of the following probes creates a beam with most divergence?
Antworten
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8 MHz
Frage 22
Frage
Which of the following probes create a beam with the most divergence?
Antworten
-
small diameter, high frequency
-
large diamter, high frequency
-
small diameter, low frequency
-
large diameter, low frequency
Frage 23
Frage
Transducer frequency and beam divergence are inversely related
Frage 24
Frage
Active element diameter and beam divergence are inversely related.
Frage 25
Frage
Mechanical scanning and linear phased arrays create sector-shaped images
Frage 26
Frage
Many active elements fire at almost the same time in mechanical scanner.
Frage 27
Frage
Many active elements fire at almost the same time in a phased array scanner.
Frage 28
Frage
Which of the following transducers is best described as mechanically steered and fixed, single focused?
Antworten
-
annular phased array
-
annular array
-
mechincal
-
linear phased
Frage 29
Frage
Which of the following is best described as mechanically steered and multi-focus?
Frage 30
Frage
Which of the following transducers creates a rectangular shaped image?
Antworten
-
annular phased array
-
linear sequential array
-
mechanical
-
linear phased
Frage 31
Frage
A linear phased array transducer has 128 crystals. How many of these crystals are fired to create a single sound beam?
Antworten
-
1
-
a small group
-
a large group
-
128
Frage 32
Frage
A linear sequential array transducer has 128 crystals. How many of these crystals are fired to create a single sound beam?
Antworten
-
1
-
a small group
-
128
-
a large group
Frage 33
Frage
In a linear phased array, what is the firing patten that steers a beam to the left or right?
Antworten
-
electronic slope
-
electronic curvature
Frage 34
Frage
In linear phased arrays, what is the firing pattern that focuses a sound beam?
Antworten
-
electronic slope
-
electonic curvature
Frage 35
Frage
There are large time delays in the firing pattern of a linear phased array transducer.
Frage 36
Frage
A machine that displays A-mode and Two- dimensional image is called a duplex scanner.
Frage 37
Frage
A machine that displays a Doppler and two-dimensional images is called a duplex scanner.
Frage 38
Frage
Which of the following improves elevational resoultion?
Frage 39
Frage
Side lobes degrade axial resolution
Frage 40
Frage
Side lobes degrade lateral resolution
Frage 41
Frage
Which of the following forms of resolution improve when frame rate increases?
Antworten
-
lateral
-
temporal
-
spatial
-
longitudinal
Frage 42
Frage
Which of the following is consistent with improved temporal resolution?
Antworten
-
color doppler
-
more grey shades
-
more detail
-
high frame rate
Frage 43
Frage
All of the following decrease temporal resolution except?
Antworten
-
lower frame rate
-
deeper imaging
-
multi-focus
-
narrow sector
Frage 44
Frage
A sonographer adjusts an ultrasound scan to double the depth of view from 5 cm to 10 cm. What happens to the frame rate?
Frage 45
Frage
A sonographer adjusts an ultrasound scan to double the depth of view fro 5 cm to 10 cm. If the frame rate remains the same which on of the following also occurs?
Frage 46
Frage
A sonographer adjusts an ultrasound machine to change the sector siz for 90 to 45 degrees. Nothing else changes. What happends to the frame rate?
Antworten
-
it is doubled
-
it remains unchaged
-
it is halved
-
it is tripled
Frage 47
Frage
A sonographer adjusts an ultrasound system to change the sector size for 90 to 45 degree. The frame rate was unchanged. What else must have happened?
Frage 48
Frage
A sonographer using a phased array ultrasound system turns off the multi-focus feature. What is the most likely consequence of this action?
Frage 49
Frage
A sonographer increases the line density from 1 line per degree of the sector to 3 lines per degree of the sector. What is the most likely consequence of this action?
Antworten
-
frame rate increases
-
temporal resolution decreases
-
imaging quality decreases
-
temporal resolution increases
Frage 50
Frage
A sonographer reduces the sector angle for 90 degrees to 30 degrees. At the same time, the ultrasound system automatically increases the lines density from 1 line per degree to 2 lines per degree. No other change is made. What will happen to the frame rate?
Antworten
-
increases
-
decreases
-
remains unchanged
Frage 51
Frage
A sonographer reduces the sector angle for 90 degrees to 30 degrees. At the same time, the ultrasound system automatically increases the lines density from 1 line per degree to 3 lines per degree. No other change are made. What will happen to temporal resolution?
Antworten
-
increases
-
decreases
-
remains unchanged
Frage 52
Frage
Which of the following is most important in determinging the frame rate of a system?
Frage 53
Frage
Which of the following is most important in determining frame rate of a system?
Frage 54
Frage
What is the frame rate if each image of the ultrasound system is created in 0.02 sec (1/50 sec)
Frage 55
Frage
What is the time needed to make a single image if the frame rate of an ultrasound system is 20 Hz?
Frage 56
Frage
The critical factor in determining frame rate, line density, and imaging depth is the tranducer style.
Frage 57
Frage
The number of lines per frame and the frame rate determine the frequency
Frage 58
Frage
The number of lines per frame and frame rate determine the PRF
Frage 59
Frage
If the imaging depth of a scan is 15 cm and there are 100 lines in the image, then the number of pulses making up the scan is 1500.
Frage 60
Frage
If the imaging depth of a scan is 15 cm and there are 100 lines in the image, then the number of pulses making up the scan is 100.
Frage 61
Frage
If 100 scan lines make up an image and the frame rate is 30 per second, then the transducer's frequency is 3,000 HZ
Frage 62
Frage
If 100 scan lines make up an image and the frame rate is 30 per second, then the system's PRF is 3,000 Hz
Frage 63
Frage
When the frame is 30Hz, how long does it take to create a frame?
Antworten
-
30 sec
-
3 sec
-
0.3 sec
-
1/30 sec
-
1/3 sec
Frage 64
Frage
Under certain conditions, an ultrasound system creates imagine in 0.01 seconds. What is the frame rate?
Antworten
-
1 Hz
-
10 sec
-
100 Hz
-
200 Hz
-
0.02 Hz
Frage 65
Frage
What is the fundamental limitation of temporal resolution?
Frage 66
Frage
All of the following are components of an ultrasound system except?
Antworten
-
transducer
-
alternator
-
display
-
pulser
-
synchronizer
-
receiver
Frage 67
Frage
This type of pulser generates a constant electrical signal in the form of a sine wave
Frage 68
Frage
This type of pulser generates a single electrical spike, which ultimately creates a single sound pulse.
Frage 69
Frage
This type of pulser generates numerous electrical spikes, which ultimately create a single sound pulse
Frage 70
Frage
The acoustic power of the sound beam emitted from a transducer is determined by the ________ of the pules's signal
Antworten
-
PRF
-
Frequnecy
-
voltage
-
rectification
Frage 71
Frage
All of the following functions of the receiver except
Antworten
-
demodulation
-
supression
-
amplification
-
attenutation
Frage 72
Frage
Amplification processes all reflected signals in a similar manner
Frage 73
Frage
Compensation processes all reflected signals in a similar manner