chapter 2 questions
18. In an unfocused single element transducer, the width at the focal point of the sound beam measures how much compared to the width at the face of the transducer?
1/2
25. Which of the following is not a true statement?
A larger aperture results in a shorter near zone
45. Which of the following is not a characteristic of an unfocused single-element transducer?
At the face of the transducer, the beam diameter is twice the size of the element thickness.
23. Which of the following best describes the components of the damping material?
Epoxy resin loaded with tungsten
22. Which of the following will not affect temporal resolution?
SPL
48. Which of the following best describes the frame rate
The frame rate is equal to the pulse repetition frequency divided by the lines per frame
32. Which of the following is true concerning the frequency and the near zone length, assuming a single element unfocused transducer?
The higher the frequency, the longer the near zone
27. Which of the following is not a synonym for axial resolution?
angular
38. Which of the following shortens the length of the pulse by decreasing the number of cycles in the pulse?
backing material
20. Which of the following describes the range of frequencies present within the beam?
bandwidth
47. Which of the following is not a method of creating 3D images?
broadband technology
50. How are ultrasound transducers typically sterilized?
cold steralization
21. Which type of interference results in a higher-amplitude sound wave?
constructive
35. Which transducer has no range resolution?
continuous wave
36. Which of the following transducers is not used for imaging?
continuous wave
17. Which of the following electrical patterns produces electronic focusing of the sound beam?
curve
46. Which of the following would be best utilized for imaging structures in the abdomen?
curved sequence array transducer
2. Which of the following is part of the transducer that stops the ringing of the element?
damping material
26. Which of the following is not true of damping?
damping worsens axial resolution
Which of the following is the resolution on the third dimensional of the beam?
elevational
1. Which of the following would be considered the narrowest part of a sound beam?
focal zone
28. Temporal resolution relates to which of the following?
frame rate
34. Which of the following is not a component of spatial resolution?
frame resolution
29. Which of the following may also be referred to as the far zone?
fraunhofer zone
8. Along with crystal diameter (aperture), the divergence in the far field is also determined by which of the following?
frequency
30. What states that waves are the result of the interference of many wavelets produced at the face of the transducer?
huygens principle
10. Which of the following would cause an increase in frame rate?
increase PRF
16. Damping material produces all of the following except:
increased SPL
9. Which of the following would cause a decrease in temporal resolution
increased line density
11. Which of the following is true of the diameter of the sound beam in the Fresnel zone?
it decreases with distance from the transducer
41. What does heat sterilization do to an ultrasound transducer
kills pathogens and destroys the transducer
13. Which of the following would most likely increase the near zone length?
large crystal diameter, high frequency
14. Which of the following would most likely decrease the beam divergence in the far field?
large crystal diameter, high frequency
12. Which resolution typically has the lowest number in clinical imaging?
longitudinal
15. Imaging transducers typically have:
low Q factors, wide bandwidth
19. Which of the following facilitates the transmission of sound from the element into the patients skin?
matching layer
40. The portion of the transducer that comes in contact with the patient is the
matching layer
3. Along with image depth, which of the following also determines the frame rate?
number of lines per frame
5. If the depth is increased and the frame rate is unchanged, what else must have decreased?
number of lines per frame
37. Which of the following transducers is also referred to as a sector or vector transducer?
phased array
39. Which of the following produces a pie shaped image?
phased array
33. Which of the following is defined as changing the time of the shocking of the elements in order to shape and steer the beam?
phasing
42. Which of the following is defined as the minimum distance two reflector can be, parallel to the beam, and still appear on the screen as 2 dots?
range resolution
6. Which of the following transducers can be described as having the scan lines originate from a common point of origin?
sector
4. Which type of resolution is an accurate representation of moving structures?
temporal resolution
49. Which of the following is represented as time, or the ability to display structures in real time?
temporal resolution
24. Which of the following is not true of the linear sequenced array transducer
the elements are arragned in a ring
43. Which of the following describes the result of destructive interference
the resulting wave is smaller than the original wave
7. Which of the following is not a true statement about a mechanical transducer?
there are no moving parts
44. To produce a transducer with a higher frequency one should:
use a thinner PZT
