X-ray Physics Final Exam questions

1. In what year were x-rays discovered?

A. 1892

B. 1895

C. 1898

D. 1901

B

2. In what year were some of the biologically damaging effects of x-rays discovered?

A. 1892

B. 1895

C. 1898

D. 1901

C

3. X-rays were discovered in experiments dealing with electricity and _____________?

A. Ionization

B. Magnetism

C. Atomic structure

D. Vacuum tubes

D

4. X-rays were discovered when they caused a barium platinocyanide-coated plate to _________?

A. Fluoresce

B. Phosphoresce

C. Vibrate

D. Burn and redden

A

5. X-radiation is part of which spectrum?

A. Radiation

B. Energy

C. Atomic

D. Electromagnetic

D

6. X-rays have a dual nature, which means that they behave like both _________.

A. Atoms and molecules

B. Photons and quanta

C. Waves and particles

D. Charged and uncharged particles

C

7. The wavelength and frequency of x-rays are ________________ related.

A. Directly

B. Inversely

C. Partially

D. Not

B

8. X-rays have ________________ electrical charge.

A. A positive

B. A negative

C. An alternately positive and negative

D. No

D

9. X-rays have _________________.

A. No mass

B. The same mass as electrons

C. The same mass as protons

D. The same mass as neutrons

A

10. The x-ray beam used in diagnostic radiography can be described as being _________________.

A. Homogeneous

B. Monoenergetic

C. Polyenergetic

D. Scattered

C

11. Which x-ray tube component serves as a source of electrons for x-ray production?

A. Focusing cap

B. Filament

C. Stator

D. Target

B

12. Electrons interact with the ____________ to produce x-rays and heat.

A. Focusing cap

B. Filament

C. Stator

D. Target

D

13. The cloud of electrons that forms before x-ray production is referred to as ____________.

A. Thermionic emission

B. Space charge

C. Space charge effect

D. Tube current

B

14. The burning or boiling off of electrons at the cathode is referred to as _______________.

A. Thermionic emission

B. Space charge

C. Space charge effect

D. Tube current

A

15. Which primary exposure factor influences both the quantity and the quality of x-ray photons?

A. mA

B. mAs

C. kVp

D. Exposure time

C

16. The unit used to express tube current is __________.

A. mA

B. mAs

C. kVp

D. s

A

17. What percentage of the kinetic energy is converted to heat when moving electrons strike an anode target?

A. 1%

B. 25%

C. 59%

D. 99%

D

18. The intensity of the x-ray beam is greater on the __________.

A. Cathode side of the tube

B. Anode side of the tube

C. Short axis of the beam

D. Long axis of the beam

A

19. According to the line focus principle, as the target angle decreases, the ______________.

A. Actual focus spot size decreases

B. Actual focus spot size increases

C. Effective focus spot size decreases

D. Effect focus spot size increases

C

20. ________________ extends x-ray tube life.

A. Selecting higher tube currents

B. Using small focal spots when possible

C. Producing exposures with a wide range of kVp values

D. Warming up the tube after 2 hours of nonuse

D

21. Which type of target interaction is responsible for most of the x-rays in the diagnostic beam?

A. Characteristic interaction

B. Thermionic emission

C. Bremsstrahlung interaction

D. None of the above

C

22. How much mAs is produced when the radiographer sets 70kVp, 600 mA, and 50 ms?

A. 3.5 mAs

B. 30 mAs

C. 300 mAs

D. 350 mAs

B

23. Increasing the kVp results in ____________.

A. X-rays with higher energy

B. X-rays with lower energy

C. More x-rays

D. A and C

E. B and C

D

24. Total filtration in the x-ray beam includes ___________.

A. Compensating filters

B. Inherent filtration

C. Added filtration

D. B and C

E. All of the above

D

25. How many heat units result from an exposure made on a single-phase x-ray unit using 400 mA, 0.2 second, and 70 kVp?

A. 5600 HU

B. 7560 HU

C. 7896 HU

D. 8120 HU

A

26. The process whereby a radiographic image is created by variations in absorption and transmission of the exiting x-ray beam is known as _____________.

A. Attenuation

B. The photoelectric effect

C. The Compton effect

D. Differential absorption

D

27. Which of the following processes occur during the x-ray beam interaction with tissue?

1. (1) Absorption

2. (2) Photon transmission

3. (3) Scattering

A 1 and 2 only

B 1 and 3 only

C 2 and 3 only

D 1, 2, and 3

D

28. The ability of an x-ray photon to remove an atom's electron is a characteristic known as __________.

A. Attenuation

B. Scattering

C. Ionization

D. Absorption

C

29. The x-ray interaction responsible for absorption is _____________.

A. Differential

B. Photoelectric

C. Attenuation

D. Compton

B

30. The x-ray interaction responsible for scattering is _____________.

A. Differential

B. Photoelectric

C. Attenuation

D. Compton

D

31. Remnant radiation is composed of which of the following?

1. (1) Transmitted radiation

2. (2) Absorbed radiation

3. (3) Scattered radiation

A. 1 and 2 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2, and 3

B

32. What interaction creates unwanted exposure to the image, known as fog?

A. Compton

B. Transmitted

C. Photoelectric

D. Absorption

A

33. Which of the following factors would affect beam attenuation?

1. (1) Tissue atomic number

2. (2) Beam quality

3. (3) Fog

A. 1 and 2 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2, and 3

A

34. The low-density or high brightness areas on a radiographic image are created by _____________.

A. Transmitted radiation

B. Scattered radiation

C. Absorbed radiation

D. Primary radiation

C

35. An anatomic part that transmits the incoming x-ray photon would create an area of _____________ on the radiographic image.

A. Fog

B. Low density or high brightness

C. High density or low brightness

D. Gray

C

36. The process of creating a radiographic image by differential absorption varies for film-screen and digital imaging.

A. True

B. False

B

37. An attribute (or attributes) of a radiographic image that affects the visibility of sharpness is ______.

A. Distortion

B. Contrast

C. Density

D. Contrast and density

D

38. A radiographic film image with many densities but little differences among them is said to have _____.

A. High contrast

B. Low contrast

C. Short-scale contrast

D. Excessive density

B

39. Which of the following is defined as the range of exposure intensities an image receptor can accurately detect?

A. Long-scale contrast

B. Spatial resolution

C. Quantum noise

D. Dynamic range

D

40. Which of the following would improve digital image quality?

A. Small matrix and large pixel size

B. Decreased pixel density and increased pixel pitch

C. Large matrix and large pixel size

D. Large matrix and increased pixel density

D

41. Which of the following is accurate regarding the relationship between milliamperage (mA) and exposure time to maintain the exposure to the image receptor?

A. Direct proportional

B. Direct

C. Inverse

D. Inverse proportional

D

42. A radiographic film image has excessive density. Which of the following is best in order to correct the exposure error?

A. Decrease kVp by 50%

B. Increase mAs by 15%

C. Decrease mAs by 50%

D. Decrease mAs by 15%

C

43. What exposure factor affects both the quality and the quantity of the x-ray beam?

A. kVp

B. SID

C. mA

D. Focal spot size

A

44. Which of the following is NOT affected by kilovoltage?

A. Compton interactions

B. Spatial resolution

C. Film density

D. Radiation quantity

B

45. How is the quality of the image affected when more than needed radiation exposure reaches the digital image receptor?

A. No effect

B. Decreased brightness

C. Increased brightness

D. Higher contrast

A

46. Which of the following would maintain radiation exposure to the image receptor when the kilovoltage is decreased by 15%?

A. Increase mAs by 15%

B. Increase mAs by 50%

C. Double the mAs

D. Halve the mAs

C

47. A quality image is produced using 70 kVp and 25 mAs at a 40-inch SID. What calculated change in exposure technique is necessary to maintain radiation exposure to the image receptor when the SID is increased to 56 inches?

A. 60 kVp at 25 mAs

B. 70 kVp at 12.5 mAs

C. 70 kVp at 50 mAs

D. 60 kVp at 50 mAs

C

48. Without exposure technique compensation, increasing the OID by 4 inches for a knee film image would:

1. (1) Increase magnification

2. (2) Decrease Density

3. (3) Increase contrast

A. 1 and 2 only

B. 1 and 3 only

C. 2 and 3 only

D. 1, 2, and 3

D

49. A quality image is produced using 80 kVp at 10 mAs with a 6:1 ratio grid. Calculate the change in exposure technique to maintain radiation exposure to the image receptor when changing to a 12:1 ratio grid.

A. 80 kVp at 17 mAs

B. 68 kVp at 20 mAs

C. 80 kVp at 6 mAs

D. 92 kVp at 5 mAs

A

50. Which of the following factors does not affect the radiation exposure to the image recptor?

A. Collimation

B. Focal spot size

C. Compensating filters

D. Body habitus

B

51. What exposure factor change is recommended to maintain radiation exposure to the image receptor when increasing patient thickness by 5 cm?

A. Double the kVp

B. Double the mAs

C. Decrease kVp by 15%

D. Increase mAs by 15%

B

52. Instilling a negative contrast agent in the gastrointestinal tract has what effect in the area of interest on the digital image?

A. Increased brightness

B. Decreased contrast

C. Decreased brightness

D. No effect

C

53. The projected shape of the unrestricted primary beam is _________________.

A. Square

B. Rectangular

C. Circular

D. Elliptical

C

54. A purpose of beam-restricting devices is to _____________ by changing the size and shape of the primary beam.

A. Increase patient dose

B. Decrease scatter radiation produced

C. Increase exposure to the image receptor

D. Decrease image contrast

B

55. The most effective type of beam-restricting device is them ____________.

A. Cone

B. Aperture diaphragm

C. Cylinder

D. Collimator

D

56. Of the beam-restricting devices listed in the previous question, which two are most similar to one another?

A. A and B

B. A and C

C. B and C

D. B and D

B

57. The purpose of automatic collimation is to ensure that ______________.

A. The quantity of scatter production is minimal

B. The field size does not exceed the image receptor size

C. Maximal recorded detail and contrast are achieved

D. Exposure to the image receptor is maintained

B

58. When making a significant increase in collimation, _______________.

A. mAs should be increased

B. kVp should be increased

C. mAs should be decreased

D. kVp should be decreased

A

59. Which one of the following increases as collimation increases?

A. Patient exposure

B. Scatter production

C. Fog

D. Contrast

D

60. Which of the following statements is true of positive beam-limiting devices?

A. They are required on all radiographic installations

B. They are required on all new radiographic installations

C. They have never been required on radiographic installations

D. They were once requires on new radiographic installations

D

61. The purpose of a grid in radiography is to ________________.

A. Increase exposure to the image receptor

B. Increase image contrast

C. Decrease patient dose

D. Increase recorded detail

B

62. Grid ratio is defined as the ratio of the ___________________.

A. Height of the lead strips to the distance between them

B. Width of the lead trips to their height

C. Number of lead strips to their width

D. Width of the lead strips to the interspace material

A

63. Compared with parallel grids, focused grids __________.

A. Have a greater grid frequency and lead content

B. Can be used with either side of facing the tube

C. Have a wider range of grid ratios and frequencies

D. Allow more transmitted photons to reach the image receptor

D

64. With which one of the following grids would a convergent line be formed if imaginary lines from its grid lines were drawn in space above it?

A. Linear focused

B. Crossed focus

C. Linear parallel

D. Crossed parallel

A

65. If 15 mAs is used to produce a particular level of exposure to the image receptor without a grid, what mAs would be needed to produce that same level of exposure using a 16:1 grid?

A. 45

B. 60

C. 90

D. 105

C

66. Grid cutoff, regardless of the cause, is most recognizable on a film radiograph as reduced _________.

A. Contrast

B. Recorded detail

C. Density

D. Positioning

C

67. Off-focus grid cutoff occurs by using as SID that is not ______________.

A. Within the focal range of the grid

B. Equal to the focal distance of the grid

C. At the level of the convergent line of the grid

D. At the level of the convergent point of the grid

A

68. The type of motion most used for moving grids today is ______________.

A. Longitudinal

B. Reciprocating

C. Circular

D. Single stroke

B

69. A grid should be used whenever the anatomic part size exceeds _________.

A. 3 cm

B. 6 cm

C. 10 cm

D. 12 cm

C

70. The air gap technique uses an increased _______ instead of a grid.

A. kVp

B. mAs

C. SID

D. OID

D

71. The type of image receptor that uses a photostimulable phosphor to acquire the latent image is ___________.

A. An intensifying screen

B. A flat panel detector

C. Computed radiography

D. Radiographic film

C

72. Which of the following is used to extract the latent image from an imaging plate?

A. Laser beam

B. Photomultiplier tube

C. Analog-to-digital converter

D. Thin-film transistor

A

73. Which of the following will improve the quality of the digital image?

A. Decreased sampling frequency and increased sampling pitch

B. Decreased sampling frequency and decreased sampling pitch

C. Increased sampling frequency and increased sampling pitch

D. Increased sampling frequency and decreased sampling pitch

D

74. Which of the following would improve the quality of the digital image for a given field of view (FOV)?

A. A fixed matrix size and larger imaging plate

B. A decreased sampling frequency and larger imaging plate

C. A small matrix size and larger pixel size

D. A fixed matrix size and small imaging plate

D

75. What is the process of assigning a numeric value to represent a brightness value?

A. Dynamic range

B. Signal-to-noise ratio

C. Quantization

D. Spectral sensitivity

C

76. Which of the following pixel bit depths would display a greater range of shades of gray to represent the anatomical tissues?

A. 8-bit

B. 10-bit

C. 14-bit

D. 16-bit

D

77. Digital imaging systems have a wider dynamic range than film-screen image receptors.

A. True

B. False

A

78. A lower signal-to-noise ratio improves the quality of a digital image.

A. True

B. False

B

79. Which of the following is the latent image center for radiographic film?

A. Phosphor layer

B. Polyester base

C. Detector element

D. Sensitivity speck

D

80. Which of the following describes a film's sensitivity to x-rays or light?

A. Gamma

B. Speed

C. Contrast

D. Latitude

B

81. Intensifying screens are used to _____________.

A. Decrease patient exposure

B. Increase recorded detail

C. Increase film latitude

D. Decrease contrast

A

82. The ability to emit light only when stimulated by x-rays is known as ________________.

A. Phosphorescence

B. Sensitometry

C. Conversion efficiency

D. Fluorescence

D

83. Which of the following is defined as a graphic representation of the pixel value?

A. Automatic rescaling

B. Values of interest

C. Histogram

D. Exposure indicator

C

84. What process is employed to maintain consisten digital image brightness for overexposure or under exposure

A. Automatic rescaling

B. Histogram

C. Exposure indicator

D. Lookup tables

A

85. Which of the following is NOT a numeric value indicating the level of radiation exposure to the digital image receptor?

A. Sensitivity number

B. Exposure indicator

C. Window level

D. Exposure index

C

86. What digital process alters image brightness and grayscale to improve the visibility of an atomic automatic rescaling structures?

A. Automatic rescaling

B. Histogram analysis

C. Exposure indicator

D. Lookup tables

D

87. What type of monitor passes light through liquid crystals to display the digital image?

A. TFT

B. LCD

C. CRT

D. PACS

B

88. Maintaining a low level of ambient lighting can improve soft copy viewing of digital images.

A. True

B. False

A

89. Display monitors used for soft copy viewing of digital images should have ________________.

A. Increased ambient lighting

B. Decreased matrix size

C. Low spatial resolution

D. High luminance

D

90. Which of the following is not a function during postprocessing of the displayed digital image?

A. Automatic rescaling

B. Electronic collimation

C. Windowing

D. Edge enhancement

A

91. A wider window width ________.

A. Increases brightness

B. Decreases brightness

C. Increases contrast

D. Decreases contrast

D

92. What reducing agent acts slowly to produce the higher densities on a film radiograph?

A. Ammonium thiosulfate

B. Hydroquinone

C. Phoenix one

D. Cesium iodide

B

93. What chemical agent is responsible for clearing the unexposed silver halide crystals during film processing?

A. Ammonium thiosulfate

B. Hydroquinone

C. Phenidone

D. Cesium iodide

A

94. How is the archival quality of radiographic film maintained?

A. Remove most of the fixing agent from the film

B. Retain at least 10% moisture in the film

C. Store film in an area of high humidity

D. A and B only

D

95. Which automatic processing system primarily maintains the activity level of the chemistry?

A. Replenishment

B. Standby control

C. Recirculation

D. Quality control

A

96. Why is silver recovery necessary during film processing?

A. It is a natural resource

B. Is it toxic to the environment

C. It has monetary value

D. All of the above

D

97. Film radiographs are best viewed on illuminators having variability of light intensity.

A. True

B. False

B

98. AEC devices work by measuring ____________.

A. Radiation leaving the tube

B. Radiation that exits the patient

C. Radiation that is absorbed by the patient

D. Attenuation of primary radiation by the patient

B

99. How many detectors are typically found in an AEC system?

A. One

B. Two

C. Three

D. Four

C

100. Minimum response time referees to ________.

A. The proper exposure time needed for an optimal exposure when an AEC device is used

B. Exposure time minus the amount of time the AEC detectors are measuring radiation

C. The difference in exposure times between AEC systems and electronic timers

D. The shortest exposure time possible when an AEC device is used

D