Questão 1
Questão
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?
Responda
-
increases
-
decreases
-
no change
Questão 2
Questão
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?
Responda
-
increases
-
decreases
-
no change
Questão 3
Questão
The frequency of a transducer does not change. If the diameter of the new piezoelectric crystals increases, what happens to wavelength?
Responda
-
increases
-
decreases
-
no change
Questão 4
Questão
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?
Responda
-
increases
-
decreases
-
no change
Questão 5
Questão
At the location is the sound beam diameter three time greater than the transducer diameter?
Responda
-
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
Questão 6
Questão
What is the shape of a sound beam created by a tiny piece of PZT?
Responda
-
hourglass shaped
-
V-shaped
-
round
-
shaped like a tube
Questão 7
Questão
Which of the following explains why a sound beam created by a disc-shaped crystal is hourglass-shaped?
Responda
-
Bernoulli's Principle
-
Sheffield's Law
-
Ohm's Law
-
Huygen's Principle
Questão 8
Questão
Which of the following locations is the deepest?
Questão 9
Questão
Which of the following locations is the most shallow?
Responda
-
beginning of the far zone
-
beginning of the focal zone
-
focal depth
-
beginning of the Fraunhofer zone
Questão 10
Questão
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?
Questão 11
Questão
A pair of 9mm diameter probes are identical except for frequency, which is 3MHZ and 6MHz. WHich beam will have shallower focus?
Questão 12
Questão
Which of the following probes creates a beam with the deepest focus?
Responda
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8MHz
Questão 13
Questão
Which of the following probes creates a beam with the shallowest focus?
Responda
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8MHz
Questão 14
Questão
Which of the following probes creates a beam with a the shallowest focus?
Responda
-
small diameter, high frequency
-
large diameter, high frequency
-
small diameter, low frequency
-
large diameter, low frequency
Questão 15
Questão
Active elements diameter and near zone are directly related?
Questão 16
Questão
Transducer frequency and near zone length are inversely related.
Questão 17
Questão
Wavelength and near zone length are inversely related.
Questão 18
Questão
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?
Questão 19
Questão
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>
Questão 20
Questão
Which of the following probes creates a beam with least divergence?
Responda
-
4 mm diameter, 4MHz
-
6 mm diameter, 8MHz
-
6 mm diameter, 2MHz
-
5 mm diameter, 8 MHz
Questão 21
Questão
Which of the following probes creates a beam with most divergence?
Responda
-
4 mm diameter, 4 MHz
-
6 mm diameter, 8 MHz
-
4 mm diameter, 2 MHz
-
5 mm diameter, 8 MHz
Questão 22
Questão
Which of the following probes create a beam with the most divergence?
Responda
-
small diameter, high frequency
-
large diamter, high frequency
-
small diameter, low frequency
-
large diameter, low frequency
Questão 23
Questão
Transducer frequency and beam divergence are inversely related
Questão 24
Questão
Active element diameter and beam divergence are inversely related.
Questão 25
Questão
Mechanical scanning and linear phased arrays create sector-shaped images
Questão 26
Questão
Many active elements fire at almost the same time in mechanical scanner.
Questão 27
Questão
Many active elements fire at almost the same time in a phased array scanner.
Questão 28
Questão
Which of the following transducers is best described as mechanically steered and fixed, single focused?
Responda
-
annular phased array
-
annular array
-
mechincal
-
linear phased
Questão 29
Questão
Which of the following is best described as mechanically steered and multi-focus?
Questão 30
Questão
Which of the following transducers creates a rectangular shaped image?
Responda
-
annular phased array
-
linear sequential array
-
mechanical
-
linear phased
Questão 31
Questão
A linear phased array transducer has 128 crystals. How many of these crystals are fired to create a single sound beam?
Responda
-
1
-
a small group
-
a large group
-
128
Questão 32
Questão
A linear sequential array transducer has 128 crystals. How many of these crystals are fired to create a single sound beam?
Responda
-
1
-
a small group
-
128
-
a large group
Questão 33
Questão
In a linear phased array, what is the firing patten that steers a beam to the left or right?
Responda
-
electronic slope
-
electronic curvature
Questão 34
Questão
In linear phased arrays, what is the firing pattern that focuses a sound beam?
Responda
-
electronic slope
-
electonic curvature
Questão 35
Questão
There are large time delays in the firing pattern of a linear phased array transducer.
Questão 36
Questão
A machine that displays A-mode and Two- dimensional image is called a duplex scanner.
Questão 37
Questão
A machine that displays a Doppler and two-dimensional images is called a duplex scanner.
Questão 38
Questão
Which of the following improves elevational resoultion?
Questão 39
Questão
Side lobes degrade axial resolution
Questão 40
Questão
Side lobes degrade lateral resolution
Questão 41
Questão
Which of the following forms of resolution improve when frame rate increases?
Responda
-
lateral
-
temporal
-
spatial
-
longitudinal
Questão 42
Questão
Which of the following is consistent with improved temporal resolution?
Responda
-
color doppler
-
more grey shades
-
more detail
-
high frame rate
Questão 43
Questão
All of the following decrease temporal resolution except?
Responda
-
lower frame rate
-
deeper imaging
-
multi-focus
-
narrow sector
Questão 44
Questão
A sonographer adjusts an ultrasound scan to double the depth of view from 5 cm to 10 cm. What happens to the frame rate?
Questão 45
Questão
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?
Questão 46
Questão
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?
Responda
-
it is doubled
-
it remains unchaged
-
it is halved
-
it is tripled
Questão 47
Questão
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?
Questão 48
Questão
A sonographer using a phased array ultrasound system turns off the multi-focus feature. What is the most likely consequence of this action?
Questão 49
Questão
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?
Responda
-
frame rate increases
-
temporal resolution decreases
-
imaging quality decreases
-
temporal resolution increases
Questão 50
Questão
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?
Responda
-
increases
-
decreases
-
remains unchanged
Questão 51
Questão
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?
Responda
-
increases
-
decreases
-
remains unchanged
Questão 52
Questão
Which of the following is most important in determinging the frame rate of a system?
Questão 53
Questão
Which of the following is most important in determining frame rate of a system?
Questão 54
Questão
What is the frame rate if each image of the ultrasound system is created in 0.02 sec (1/50 sec)
Questão 55
Questão
What is the time needed to make a single image if the frame rate of an ultrasound system is 20 Hz?
Questão 56
Questão
The critical factor in determining frame rate, line density, and imaging depth is the tranducer style.
Questão 57
Questão
The number of lines per frame and the frame rate determine the frequency
Questão 58
Questão
The number of lines per frame and frame rate determine the PRF
Questão 59
Questão
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.
Questão 60
Questão
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.
Questão 61
Questão
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
Questão 62
Questão
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
Questão 63
Questão
When the frame is 30Hz, how long does it take to create a frame?
Responda
-
30 sec
-
3 sec
-
0.3 sec
-
1/30 sec
-
1/3 sec
Questão 64
Questão
Under certain conditions, an ultrasound system creates imagine in 0.01 seconds. What is the frame rate?
Responda
-
1 Hz
-
10 sec
-
100 Hz
-
200 Hz
-
0.02 Hz
Questão 65
Questão
What is the fundamental limitation of temporal resolution?
Questão 66
Questão
All of the following are components of an ultrasound system except?
Responda
-
transducer
-
alternator
-
display
-
pulser
-
synchronizer
-
receiver
Questão 67
Questão
This type of pulser generates a constant electrical signal in the form of a sine wave
Questão 68
Questão
This type of pulser generates a single electrical spike, which ultimately creates a single sound pulse.
Questão 69
Questão
This type of pulser generates numerous electrical spikes, which ultimately create a single sound pulse
Questão 70
Questão
The acoustic power of the sound beam emitted from a transducer is determined by the ________ of the pules's signal
Responda
-
PRF
-
Frequnecy
-
voltage
-
rectification
Questão 71
Questão
All of the following functions of the receiver except
Responda
-
demodulation
-
supression
-
amplification
-
attenutation
Questão 72
Questão
Amplification processes all reflected signals in a similar manner
Questão 73
Questão
Compensation processes all reflected signals in a similar manner