Physics Flashcards
(313 cards)
1
Q
Which cell type is the most radiosensitive in the body?
a. erythrocyte
b. lymphocyte
c. megakaryocyte
d. monocyte
e. neutrophil
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p516.
A
b. lymphocyte
2
Q
How many half-value layers represent the equivalent of one tenth-value layer?
a. 1.5
b. 2.2
c. 2.75
d. 3.3
e. 5
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p547.
A
d. 3.3
3
Q
Which form of leukemia is not considered to be a form of radiation induced leukemia?
a. acute lymphocytic
b. acute myelogenous
c. chronic lymphocytic
d. chronic myelogenous
e. none of the above
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p529.
A
c. chronic lymphocytic
4
Q
Which represents a nearly tissue-equivalent radiation dosimeter? a. calcium fluoride b. calcium sulfate c. calcium tungstate d. lithium borate e. lithium fluoride Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p565.
A
e. lithium fluoride
5
Q
True or false:
Teleradiology is the process of remote transmission and viewing of images.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p330.
A
True
6
Q
True or false: Distortion is reduced by positioning the anatomical part of interest perpendicular to the plane of the image receptor. a. false b. true Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p252.
A
False
7
Q
- The 5% rule describes that an increase of kVp by 5% can be accompanied by a decrease in mAs by what percent?
a. 5
b. 15
c. 30
d. 50
e. 66
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p250.
A
c. 30
8
Q
A 15% increase in kVp accompanied by how much of a reduction in mAs creates the same optical density? a. 1/10 b. 1/5 c. ¼ d. 1/3 e. ½ Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p248.
A
½
9
Q
True or false:
A long exposure time reduces motion blur?
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p238.
A
False
10
Q
True or false:
Silver sulfide stain is the most common cause of poor archival quality.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p231.
A
True
11
Q
Scatter radiation increases as the x-ray field size _______.
a. decreases
b. increases
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p189.
A
increases
12
Q
There is a decrease in patient dose and an improvement in contrast resolution when collimation is _______.
a. large
b. small
A
small
13
Q
Compression of anatomy ______ spatial resolution. a. improves b. worsens Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p190.
A
improves
14
Q
The focal spot blur is ______ on the anode side of the image.
a. large
b. small
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p178.
A
small
15
Q
Image receptors with a wide latitude have a _____ grayscale. a. long b. short Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p172.
A
long
16
Q
X-rays with energy of 15 MeV is capable of which interaction with matter?
a. coherent scatter
b. Compton effect
c. pair production
d. photodisintegration
e. photoelectric effect
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p153.
A
photodisintegration
17
Q
The description of the photoelectric effect earned who the Nobel prize? a. Dally b. Edison c. Einstein d. Hounsfield Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p149.
A
Einstein
18
Q
Beam hardening refers to a relative ______ in average energy.
a. decrease
b. increase
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p131.
A
increase
19
Q
Which type of x-rays form a continuous emission spectrum?
a. bremsstrahlung
b. characteristic
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p128.
A
bremsstrahlung
20
Q
True or false:
Most x-rays in the diagnostic range are bremsstrahlung.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p127.
A
True
21
Q
True or false:
Ferromagnetic materials can become magnets by induction.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p73.
A
True
22
Q
True or false:
Magnetic susceptibility is the degree to which a material can be magnetized.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p72.
A
True
23
Q
True or false:
The amount of transmitted photons increases as attenuation increases.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p53.
A
False
24
Q
True or false:
Gamma rays are emitted from an electron cloud that has been artificially stimulated.
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p51.
A
False
25
Which is not a part of the electromagnetic spectrum?
a. gamma rays
b. microwaves
c. radiofrequency
d. ultrasound
e. x-rays
Bushong, Stewart. Radiologic Science for Technologists. 11th ed. p49.
ultrasound
26
Energy emitted and transferred through space best describes
a. excitation
b. frequency
c. ionization
d. magnetization
e. radiation
Bushong, S. C. (2017). Page 5
radiation
27
The removal of an electron from an atom describes
a. excitation
b. frequency
c. ionization
d. magnetization
e. radiation Bushong, S. C. (2017). Page 5
ionization
28
Which is an electromagnetic radiation form which can ionize?
a. infrared light
b. microwaves
c. visible light
d. radiowaves
e. x-rays
Bushong, S. C. (2017). 11th ed Page 6
x-rays
29
Which is a way to protect x-ray equipment operators from radiation exposure?
a. appropriate film-screen combination
b. collimation
c. filtration
d. shielding
e. using a high kVp
Bushong, S. C. (2017). 11th ed. Page 605
shielding
30
The **risk of childhood leukemia is increased by what percentage if a fetus is irradiated in utero**?
a. 20%
b. 30%
c. 40%
d. 50%
e. 60%
Bushong, S. C. (2017). 11th ed. Page 536
50%
31
What is the genetically significant dose value in the United States?
a. 100rem
b. 100mSv
c. 150mGy
d. 200rad
e. 200mGy
Bushong, S. C. (2017). 11th ed. Page 572
200mGy
32
Which type of leukemia is not considered a radiation induced leukemia?
a. acute lymphocytic leukemia
b. acute myelogenous leukemia
c. chronic lymphocytic leukemia
d. chronic myelogenous leukemia
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 529
chronic lymphocytic leukemia
33
**Permanent epilation** occurs with radiation doses of
a. 2Gy
b. 5Gy
c. 7Gy
d. 9Gy
e. 10Gy
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection, pg. 513
7Gy
34
Which **radiation dose-response relationship** is **described as having a response which is directly proportional to the dose**?
a. linear
b. non-linear
c. threshold
d. non-threshold
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 487
linear
35
Which radiation dose - response relationship suggests that any dose is expected to produce a response?
a. linear
b. non-linear
c. threshold
d. non-threshold
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 488
non-threshold
36
**Rayleigh-Tyndall scattering** in sonography is due to
a. an inadequate Fresnel zone.
b. an enlarged Fraunhoffer zone.
c. inadequate transducer contact.
d. the presence of calcium in the visualized
anatomy.
e. red blood cells.
Curry, T. S. Dowdey, J. E. Murray, R. C. (1990). **Christensen’s Physics of Diagnostic Radiology**. 4th ed. Malvern, PA: Lea & Febiger. Page 355.
red blood cells
37
The **CT characterized by a rotating x-ray tube and a couch which moves the patient through the rotating beam** describes a
a. first generation CT.
b. second generation CT.
c. third generation CT.
d. multislice helical
CT. Bushberg, J. T. Seibert, J. A. Leidholdt, E. M. Boone, J. M. The Essential Physics of Medical Imaging. (2012. 3rd. ed. Philadelphia, PA: Lippincott Williams & Wilkins. Page 337.
multislice helical CT.
38
Ring artifacts are seen on CT images due to the use of a rotate-rotate scanner. This scanner was seen in which generation of CT?
a. first generation CT
b. second generation CT
c. third generation CT
d. fourth generation
Curry, T. S. Dowdey, J. E. Murray, R. C. (1990). **Christensen’s Physics of Diagnostic Radiology**. 4th ed. Malvern, PA: Lea & Febiger. **Page 320.**
third generation CT
39
The relationship between the patient couch movement and the x-ray beam width in CT is known as the
a. interpolation.
b. gantry ratio.
c. piezoelectric effect.
d. pitch.
e. Q factor.
Bushberg, J. T. Seibert, J. A. Leidholdt, E. M. Boone, J. M. The Essential Physics of Medical Imaging. (2012. 3rd. ed. Philadelphia, PA: Lippincott Williams & Wilkins. Page 338.
pitch
40
The purity of sound and length of time sound persists with regard to the crystal in an ultrasound transducer is known as the
a. interpolation.
b. gantry ratio.
c. piezoelectric effect.
d. pitch.
e. Q factor.
Curry, T. S. Dowdey, J. E. Murray, R. C. (1990). **Christensen’s** Physics of Diagnostic Radiology. 4th ed. Malvern, PA: Lea & Febiger. **Page 330.**
Q factor.
41
What is **cinefluorography most commonly used to image**?
a. bones
b. bowel
c. brain
d. heart
e. lungs
Curry, T. S. Dowdey, J. E. Murray, R. C. (1990). **Christensen’s Physics of Diagnostic Radiology.** 4th ed. Malvern, PA: Lea & Febiger. **Page 189.**
heart
42
How can motion blur be avoided when taking radiographs of a patient?
a. decreasing kVp
b. increasing exposure time
c. using a large OID
d. using a small SID
e. using a breath hold
**Bushong**, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. **Page 181**
using a breath hold\*
43
How can penumbra be reduced when taking radiographs?
a. decreasing kVp
b. decreasing SID
c. increasing mAs
d. increasing OID
e. using a small focal spot
**Curry, T. S. Dowdey, J. E. Murray, R. C. (1990). Christensen’s** Physics of Diagnostic Radiology. 4th ed. Malvern, PA: Lea & Febiger. **Page 225.**
using a small focal spot
44
Which step of radiographic film processing removes unexposed silver halide crystals?
a. development
b. drying
c. fixing
d. stop bath
e. washing
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. **Page 230**
fixing
45
A 20-year-old radiographic film has turned a yellow-brown color. What is the most likely cause?
a. expiration of developing agents
b. fixer retention
c. inadequate developing
d. normal film aging
e. oxidation of the developer
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 231
fixer retention
46
The silver halide in the radiographic film emulsion layer is mostly made of
a. silver bromide
b. silver iodide
c. silver nitrate
d. silver oxide e. silver sulfide
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 209
a. silver bromide
47
**Fixer retention leads to the development** of which compound?
a. silver bromide
b. silver iodide
c. silver nitrate
d. silver oxide
e. silver sulfide
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 231
e. silver sulfide
48
Which is **true regarding the performance of the air-gap technique** during radiographic examination?
a. kVp should be increased by 25% for every 1cm
increase in OID
b. mAs must be increased by 10% for every 1cm
increase in OID
c. mAs must decrease by a factor of 2 for every
2cm increase in OID
d. no changes are needed in kVp or mAs
e. The technique can only be used with a kVP
greater than 100.
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 204
b. mAs must be increased by 10% for every 1cm increase in OID
49
If a patient is properly exposed at 40 inches SID with a mAs of 20 what must the mAs be if the SID is changed to 72 inches?
a. 35
b. 50
c. 60
d. 65
e. 70
Bushong, S. C. (2017). Radiologic science for technologists: Physics, biology, and protection. St. Louis, MO: Elsevier. Page 240
d. 65
50
To **prevent a female accidentally exposing an embryo to radiation during the early stages** of pregnancy, the radiographer should \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. only irradiate her during the last 10 days of her menstrual period
b. never irradiate a female for any reason
c. do it whenever, because it isn't that much radiation
d. only irradiate her during the first 10 days of her menstrual period
d. **only irradiate her during the first 10 days of her menstrual period**
51
When x-raying females, the radiographer is expected to:
a. employ the stochastic principle
b. follow the 10 day rule
c. use only high LET radiation
d. do all of the above
b. follow the 10 day rule
52
The number of photons in the beam is influenced by\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. mA
b. Time
c. kVp
d. all of the above
d. all of the above
53
Which of the following influences the photon energy of the beam?
a. mA b. Time c. kVp all d. of the above
c. kVp
54
The uneven distribution of radiation from one end of the x-ray field to the other is due to the \_\_\_\_\_\_\_.
a. line focus principle
b. inverse square law
c. heel effect
d. larger anode angle
c. heel effect
55
Which of the following is **NOT a method for reducing the production of scatter** radiation?
a. Patient compression
b. Beam restricting device
c. Having the patient lie down
d. Increasing the mAs
d. Increasing the mAs
56
Which of the following is **NOT a method of restricting the x-ray beam**?
a. Cone
b. Aperture
c. Grid
d. Positive beam limiting device
c. Grid
57
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is the **principle disadvantage of using an aperture to limit the size of the x-ray field**.
a. Large penumbra
b. Decreased kvp
c. Being too simple a device
d. Because it can only be used at a large FFD
a. Large penumbra
58
The best method for restricting x-ray field size is the \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. aperture
b. collimator
c. cone
d. cylinder
b. collimator
59
A positive beam limiting device is \_\_\_\_\_\_\_\_\_\_\_\_.
a. an automatic collimator
b. an automatic grid
c. a form of cylinder
d. any form of beam restrictor
a. an automatic collimator
60
A d**evice that shows a light on the patient in order to aim the x-ray beam** and also serves to limit the size of the x-ray field is called a \_\_\_\_\_\_\_\_\_\_\_.
a. grid
b. collimator
. cone
d. bucky
b. collimator
61
Modern collimators have two sets of shutters in each direction for what purpose?
a. Prevent shoot-through by the primary beam
b. Redundancy in case one set fails
c. Clean up penumbra
d. All of the above are correct
c. Clean up penumbra
62
If you wanted to **test the accuracy of your collimator**, which test would you perform?
a. Mesh screen test
b. Bucky's diagnostic exam
c. Paper clip test
d. Determine the half value layer (HVL)
c. Paper clip test
63
Radiation effects within the cell are \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. definite and predictable
b. selective and definite
c. selective and indefinite
d. random and non-selective
d. random and non-selective
(Stochastic)
64
The biologic effects of radiation that occur in living cells are \_\_\_\_\_\_\_\_\_\_.
a. always immediate
b. unique to radiation damage
c. always after some latent period
d. usually delayed only a few seconds
c. always after some latent period
65
The direct effects of radiation include:
a. damage to DNA
b. radiolysis of water
c. production of free radicals
d. none of the above
a. damage to DNA
66
Which of the following molecules in the cell are most sensitive to radiation?
a. Protein
b. DNA
c. Enzymes
d. All of these are equally sensitive
b. DNA
67
The **interaction of a photon with water producing a free radical to damage the internal portions of a cell** is \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. a form of indirect damage
b. direct damage
c. a normal process
d. none of the above
a. a form of indirect damage
68
Regarding the indirect mechanism of cellular radiation damage, in which stage do free radicals react to form new molecules?
a. Physical stage
b. Physio-chemical stage
c. Chemical stage
d. Biologic stage
c. Chemical stage
69
The rate at which energy is deposited into matter by radiation is the \_\_\_\_\_\_\_\_\_\_.
a. SED
b. LET
c. RAD
d. Roentgen
b. LET
70
The principle that states the younger immature cells are most radiosensitive is \_\_\_\_\_\_\_.
a. Law of Bergonie & Tribondeau
b. Law of Bergman & Bordeaux
c. Gray & Sievert
d. Kassabian & Dally
a. Law of Bergonie & Tribondeau
71
Which of the following is **NOT an effect on the embryo & fetus** from radiation?
a. Lethality
b. Congenital abnormality
c. Long term effects that develop in life
d. All of the above are effects of radiation
d. All of the above are effects of radiation
72
An embryo is most sensitive to death if exposed to radiation during which stage of development?
a. Major organogenesis
b. Fetal stage
c. Pre-implantation
d. Vegetative-intermitotic stage
c. Pre-implantation
73
The **effects of irradiation** during the **fetal stage** are usually:
a. lethal
b. congenital abnormality
c. retinoblastoma
d. sterility & other late effects
d. sterility & other late effects
74
An **effect in which the probability of occurance increases** **with increasing absorbed dose**, but the **severity of the effect does not increase with dose** is defined as:
a. stochastic effect
b. non-stochastic effect
c. law of Bergonie & Tribondeau
d. Non-random event
a. stochastic effect
75
A somatic effect that increases in severity with increasing absorbed dose is known as a ______________ effect.
a. stochastic
b. non-stochastic
c. random
d. characteristic
b. non-stochastic
76
Of the following, which one is **considered a stochastic effect**?
a. Genetic alteration
b. Lens opacification
c. Blood changes
d. Decreased sperm production
a. Genetic alteration
77
The paper clip test will determine \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. the screen film contact
b. focal spot size
c. grid cutoff
d. proper collimator alignment
d. proper collimator alignment
78
Which form of beam restriction has an extended metal tube structure to limit the size of the x-ray field?
a. Aperture diaphragm
b. Cylinder
c. Collimator
d. All of the above
b. Cylinder
79
CT utilizes what to create its images?
a. A big magnet
b. Technetium 99
c. X-rays
d. None of the above
c. X-rays
80
In CT imaging, the setting of how the gray scale is displayed for reading is called, what?
a. Windowing
b. Weighting
c. Withering
d. Contrasting
a. Windowing
81
According to what was said in class, which form of imaging is preferred for seeing fractures of the posterior elements of the spine?
a. MRI
b. CT
c. Bone scanning
d. Radiography
b. CT
82
A darkroom is used to process film, for what reason?
a. To refrigerate the latent image until processed
b. To make enough fog for a well exposed film
c. To prevent fogging of the film by other radiation or visible light
d. None of the above
c. To prevent fogging of the film by other radiation or visible light
83
Which statement about **film fog is TRUE**?
a. Fog is desirable for adequate density
b. Fog is created by complete darkness and controlled temperatures
c. Fog can be removed by the film processor
d. Fog contributes to image noise and is undesirable
d. Fog contributes to image noise and is undesirable
84
True or False
A safelight can fog film.
True
85
Which of the following is **NOT used in making a darkroom light tight**?
a. Maze
b. Revolving door
c. Window
d. Weather stripping
c. Window
86
Of the following, which is **NOT a requirement for a radiographic darkroom**?
a. Safelight
b. Overhead light
c. Film storage bin
d. Viewbox
d. Viewbox
87
Which of the following is a variable that affects film detail?
a. ma
b. kvp
c. time
d. focal spot size
d. focal spot size
88
The effective focal spot appears smaller than the actual focal spot because of \_\_\_\_\_\_\_\_\_\_.
a. the line-focus principle
b. the heal effect
c. the object-film distance
d. grid ratio
a. the line-focus principle
* **_Line focus princi_****_ple_ explains the relationship between the anode surface and the effective focal spot size**.
* The focal spot is the area of the target upon which the electron beam impinges. The energy of the electrons in the electron beam is mostly converted into heat (approx 99% ) and dissipated uniformly across the focal spot and anode surface.
* The x-rays produced at the anode comprise of less than one percent of the energy of the electrons in the electron beam.
* A **large focal spot is useful to protect the tungsten target as the heat accumulates and dissipates** within the area of focal spot. **_However_**, a **small focal spot is required to achieve a good radiographic image quality**
****Thus the **line focus principle helps resolve this issue by stating that an angulation of the anode surface will result in an apparent decrease in the focal spot size**.
89
The **region at the edge of an object that appears unsharp (less detailed) because the many x-ray "point sources" from the focal spot overlap** there is called what?
a. Line focus principle
b. Heel effect
c. Penumbra
d. Umbra
c. Penumbra
90
To **calculate the size of the focal spot**, which test would you perform?
a. Resolution chart
b. Star diagram
c. Slit test
d. Pinhole test
d. Pinhole test
91
What is the most common type of distortion?
a. Foreshortening
b. Elongation
c. Motion
d. None of the above
b. Elongation
92
In order to minimize magnification on an image, you would do which of the following?
a. Decrease OFD, and decrease FFD
b. Decrease OFD, and increase FFD
c. Increase OFD, and decrease FFD
d. Increase OFD, and increase FFD
b. Decrease OFD, and increase FFD
93
Which of the following is a **TRUE statement about the geiger counter**?
a. It is good for detecting particulate radiation
b. It permanently stores a count of all radiation encountered
c. It uses a gas filled tube and is portable
d. It determines the energy level of encountered radiation
c. It uses a gas filled tube and is portable
94
A TLD is a detector that \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. uses fluorescence
b. is a pocket dosimeter
c. has a higher voltage than the geiger counter
d. All of the above are true about the TLD
a. uses fluorescence
95
The type of radiation dose monitoring device that measures the total blackness of a piece of film is called a \_\_\_\_\_\_\_\_\_\_\_\_\_.
a. TLD
b. film badge
c. pocket geiger
d. film shield
b. film badge
96
With regard to ionization chambers, the greater the voltage \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. the greater the specificity
b. the less the sensitivity
c. the greater the sensitivity
d. the less the specificity
c. the greater the sensitivity
97
The **principle disadvantage of using an air-gap technique** is:
a. increased dose
b. decreased FFD
c. increased kVp
d. increased OFD
d. increased OFD
98
Electrical current is measured in \_\_\_\_\_\_\_\_\_\_.
a. Volts
b. Amperes
c. Roentgens
d. Ohms
b. Amperes
99
Substances that permit the easy flow of electrons are \_\_\_\_\_\_\_\_\_\_\_\_.
a. insulators
b. shells
c. ionizers
d. conductors
d. conductors
100
Glass is an example of, what?
a. A substance that easily permits electrons to travel. b. A substance that does not easily permit electrons travel.
c. An anode target material.
d. A low resistance material.
b. A substance that does not easily permit electrons travel.
101
Electrical resistance is governed by \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. Ohm's law
b. Planck's constant
c. Grenz principle
d. Boyle's law
a. Ohm's law
102
The difference in electrical potential as measured at different points of a circuit is called the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. amperage
b. power
c. voltage
d. resistance
c. voltage
103
An electrical current that oscillates between two directions is called, what?
a. Direct current (DC)
b. Alternating current (AC)
c. A rock band (AC/DC)
d. Transformed
b. Alternating current (AC)
104
A device that converts AC to DC is called a \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. rectifier
b. alternator
c. director
d. transformer
a. rectifier
105
How are **heat units of an x-ray tube determined**?
a. Volts x resistance x watts
b. Volts x Amps x watts
c. Seconds x Volts x resistance
d. Volts x Amps x seconds
d. Volts x Amps x seconds
106
The **variation of voltage from its maximum value to some lower percentage** is called, what?
a. Phase
b. Wavelength
c. Frequency
d. Ripple
d. Ripple
107
A diode is used to, what
a. Accelerate electrons
b. Step-up voltage
c. Rectify current
d. None of the above
c. Rectify current
108
Copper wire is an example of a(n)
a. capacitor
b. transformer
c. ainsulator
d. conductor
d. conductor
109
The **conversion of current of AC to DC** is done with a(n) \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. transformer
b. rectifier
c. anode
d. converter
b. rectifier
110
A **step up transformer has a turn ratio** that is:
a. greater than 1
b. less than 1
c. equal to 1
d. none of the above
a. greater than 1
111
The curve that represents the relationship of film density and radiation exposure is called the:
a. Compton curve
b. Hunter & Dreyfus curve
c. Rayleigh & Thomson curve
d. Hurter & Driffeld curve
d. Hurter & Driffeld curve
112
The part of the characteristic curve representing the lightest possible portion is:
a. straight line portion
b. the toe
c. the shoulder
d. the top
b. the toe
113
Spectral matching refers to:
a. matching of the size of the film to the cassette
b. matching of the color sensitivity of the film with that emitted by the screen
c. matching of the ghost with our car on the haunted mansion ride at Disneyland
d. the dating service you got thrown out of
b. matching of the color sensitivity of the film with that emitted by the screen
114
The film emulsion is composed of gelatin and holds the light sensitive crystals in suspension. What are the majority of the crystals made of?
a. Silver iodide (AgI)
b. Silver bromide (AgBr)
c. Silver chloride (AgCl)
d. Silver fluoride (AgF)
b. Silver bromide (AgBr)
115
**Modern film is made with a base made of polyester.** **Before that they were made of**, what?
a. Celluose polyvinylchloride
b. Methylmethacrylate
c. Cellulose triacetate
d. Rubber
c. Cellulose triacetate
116
When something appears to be in two different locations on the film, this is due to \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. parallax
b. Gurney-Mott hypothesis
c. quantum mottle
d. big trouble in little China
a. parallax
117
The type of film used in general radiography today is
a. direct exposure film
b. duplicating film
c. screen film
d. latent film
c. screen film
118
A liberated electron in a silver halide crystal that is trapped by the sensitivity speck forms
a. a development center
b. a conduction band
c. parallax effect
d. All of the above
a. a development center
119
A **film's sensitivity to light** is referred to as its, what?
a. Density
b. Graininess
c. Speed
d. Noise
c. Speed
120
The ability to visually detect separate objects on a film is called its\_\_\_\_\_\_\_\_\_\_\_.
a. contrast
b. resolution
c. speed
d. density
b. resolution
121
The sensitivity speck of a film crystal is central to the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. Gurney-Mott hypothesis
b. quantum mottle theory
c. law of Bergonie & Tribondeau
d. None of the above
a. Gurney-Mott hypothesis
See Christtensen's pg. 140
The theory states that the formation of latent image is d/t metallic silver formed at sensitivity centres located at imperfections in structure of silver halide crystals
122
What about the **H & D curve** is responsible for film speed?
a. Straight line
b. Toe
c. Shoulder
d. Position on the X - axis
d. Position on the X - axis
123
A film that has a lot of contrast has a curve with a:
a. high shoulder
b. low curve
c. long gray scale
d. steep straight line portion
d. steep straight line portion
124
The minimum total thickness of Al equivalent (in mm) for machines with settings above 70 KVP is:
a. 0.5
b. 1.0
c. 2.5
d. 3.0
c. 2.5
125
Which of these is **NOT a process of attenuation**?
a. Photon braking
b. Absorption
c. Scatter
d. Distance
a. Photon braking
126
The **removal of low energy x-rays by the tube envelope plus 2 mm of Al is called**
a. Added filtration
b. Inherent filtration
c. Compensating filtration
d. Total filtration
d. Total filtration
127
**Filtration of low energy x-rays from the beam by the tube envelope is known as**
a. Added filtration
b. Extra filtration
c. Inherent filtration
d. Total filtration
c. Inherent filtration
128
What might you do to make an even exposure of the AP thoracic spine to compensate for variation in body thickness?
a. Use inherent filtration
b. Have the tube mounted upside down to use the heel effect
c. Use a compensating filter
d. Hang the patient upside down to take advantage of the heel effect
c. Use a compensating filter
129
The most common material to use for a compensating filter is
a. copper
b. acrylic
c. aluminum
d. lead
c. aluminum
130
**Single phase x-ray machines have how much ripple** in their **voltage**?
a. 1%
b. 30%
c. 70%
d. 100%
d. 100%
131
Which of the following generators are more efficient at producing x-rays?
a. Half rectified
b. Self rectified
c. Full rectified
d. 3-phase
d. 3-phase
132
The ripple on a single-phase fully rectified machine is \_\_\_\_\_\_\_\_\_\_.
a. 10%
b. 25%
c. 75%
d. 100%
d. 100%
133
The Grid and the Bucky are designed for the purpose of \_\_\_\_\_\_\_\_\_\_\_\_.
a. reducing the production of scatter radiation
b. decrease the contrast of the film
c. reducing the x-ray field size
d. reducing the scatter radiation that reaches the film
d. reducing the scatter radiation that reaches the film
134
Who **designed a device that moves a grid back and forth to blur grid lines**?
a. Clarence Dally
b. Gustav Bucky
c. Hollis Potter
d. William Coolidge
c. Hollis Potter
135
The person responsible for inventing the first grid was
a. Clarence Dally
b. Gustav Bucky
c. Hollis Potter
d. William Coolidge
b. Gustav Bucky
136
The most important feature of a grid that determines its ability to reduce scatter is the \_\_\_\_\_\_\_\_\_\_\_.
a. grid ratio
b. lead content
c. grid frequency
d. grid pattern
a. grid ratio
137
The **grid ratio for any given grid is determined by** comparing \_\_\_\_\_\_\_\_\_\_\_.
a. the lines per inch to the space between the lines
b. the height of the strips to the space in between
c. the height of the lead strips to the lines per inch
d. the height of the strips to the lead content
b. the height of the strips to the space in between
138
The **grid used for most general radiography purposes is** of which type?
a. Crossed
b. Parallel
c. Reciprocating
d. Focused
d. Focused
139
If extended out from the grid, the lines of a focused grid meet at an imaginary location called the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. convergent line
b. parabolic line
c. focusing cup
d. central ray
a. convergent line
140
The **principle disadvantage of using a crossed grid** is what?
a. Increased scatter reduction
b. Improved image contrast
c. Cannot use tube angulation
d. Decreased image contrast
c. Cannot use tube angulation
141
The measurement of the percentage of primary radiation transmitted through a grid is called, what?
a. Primary transmission
b. Bucky factor
c. Contrast improvement factor
d. Grid pattern
a. Primary transmission
142
The **undesirable removal of primary radiation by a grid** is called, what?
a. Collimation
b. Grid cutoff
c. Interspacing
d. Sequestering
b. Grid cutoff
143
Which of the following is **NOT a type of grid cutoff**?
a. Lateral de-centering
b. Near de-centering
c. Far de-centering
d. Crossed de-centering
d. Crossed de-centering
144
When using an air-gap technique, the radiographer must make which adjustment to reduce magnification?
a. Increase the OFD
b. Decrease the HVL
c. Increase the FFD
d. Decrease the FFD
c. Increase the FFD
145
The amount of radiation that is shot at and reaches a film with a grid divided by the amount that reaches the film without a grid and is then expressed as a percentage is the, what?
a. Bucky factor
b. Contrast improvement factor
c. Primary transmission
d. Grid frequency
c. Primary transmission
146
The person who created a method to eliminate grid lines from the image was, who?
a. Gustav Bucky
b. William Coolidge
c. Hollis Potter
d. Mihran Kassabian
c. Hollis Potter
147
In the grid, the height of the lead strips divided by the space between the strips is \_\_\_\_\_\_\_\_\_.
a. the grid frequency
b. the grid pattern
c. the grid ratio
d. not as important as the lead strip thickness
c. the grid ratio
148
Compare the two characteristic film curves presented here. Choose the correct statement.
a. Film A has less contrast than film B
b. Film A is a faster film than B
c. Film B has a more narrow latitude than film A
d. Film B is more sensitive to light than film A
b. Film A is a faster film than B
* The farther to the right that a curve is on the chart, the slower the film speed.
* **Characteristic curve** is a graph of the relationship between the amount of exposure given to a film and it's corresponding density after processing.
* A typical film characteristic curve is made by plotting density produced, against the log of exposure given (Log E).
In film radiography, the number of photons reaching the film determines how dense the film will become when other factors such as the developing time are held constant. The number of photons reaching the film is a function of the intensity of the radiation and the time that the film is exposed to the radiation.
* The term used to describe the control of the number of photons reaching the film is “exposure.”
Different types of radiographic film respond differently to a given amount of exposure. Film manufacturers commonly characterize their film to determine the relationship between the applied exposure and the resulting film density. This relationship commonly varies over a range of film densities.
**The plot is called** a film **_characteristic curve,_** **_sensitometric curve,_** **_density curve, or H and D curve (named for developers Hurter and Driffield)_**.
* "Sensitometry" is the science of measuring the response of photographic emulsions to light or radiation.
149
Film with a wide latitude will have which of the following characteristics?
a. A short gray scale
b. High contrast
c. A long gray scale
d. Shorter exposure time
c. A long gray scale
150
The primary reason for viewing x-rays as transparencies is, what?
a. A print does not represent the full range of available optical densities
b. It doesn't matter, the effect is the same
c. The transparency is just another name for a print
d. We should be viewing them as a print, we are just behind the state of the art
A print does not represent the full range of available optical densities
151
Which of the listed choices is **NOT a method of controlling heat in the tube**?
a. Using a smaller anode angle
b. Using a tube rating chart
c. Figuring the heat units for an exposure before making it
d. Low KVP and high mAs exposures
d. Low KVP and high mAs exposures
152
The uneven distribution of radiation between the cathode and anode sides of the x-ray field is called \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. heel effect
b. space charge effect
c. line focus principle
d. bremsstrahlung
a. heel effect
153
Which one of the following will cause a decrease in heel effect in a given exposure?
a. Decreasing distance to the film
b. Increasing film size
c. Larger anode angle
d. None of the above
c. Larger anode angle
154
True or False:
There is a **decrease in beam intensity at the anode side of the x-ray beam**.
.True
155
Heel effect creates which of the following situations?
a. The cathode side of the beam shows a decrease in image clarity
b. The anode side shows an increase in beam intensity
c. The anode side shows a decrease in image clarity
d. The cathode side shows a decrease in beam intensity
a. The cathode side of the beam shows a decrease in image clarity
156
\_\_\_\_\_\_\_\_\_\_\_\_\_\_was the person who discovered x-rays.
a. Coolidge
b. Crookes
c. Roentgen
d. Geiger
c. Roentgen
157
The type of tube that was being used when x-rays were first discovered was a \_\_\_\_\_\_\_\_\_\_tube.
a. Coolidge
b. Crookes
c. Geiger
d. Roentgen
b. Crookes
158
For his work with x-rays ________________ was awarded \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. Roentgen; first Nobel prize in physics
b. Roentgen; first Nobel prize in medicine
c. Geiger; first Nobel prize in physics
d. Geiger; first Nobel prize in medicine
a. Roentgen; first Nobel prize in physics
159
Which of the following is **TRUE of the Coolidge tube**?
a. It was partially evacuated.
b. It had more fluctuation in x-ray intensity than earlier tubes.
c. It used a heated cathode.
d. None of the above are true.
c. It used a heated cathode.
160
**True or False**
Modern x-ray tubes are essentially the same as the one x-rays were discovered with.
False
161
Roentgen's experiments with x-rays did NOT include which of the following?
a. His wife
b. Crookes tube
c. Coolidge tube
d. All of these were used by Roentgen
c. Coolidge tube
162
Which of the following is **TRUE regarding Roentgen**?
a. He got rich off of x-rays
b. He died of brain cancer in 1896
c. He named the new ray "X" for an unknown quantity in math.
d. He was a chiropractic patient
c. He named the new ray "X" for an unknown quantity in math.
163
The image that is waiting to be developed after exposure but before processing is called the \_\_\_\_\_\_\_\_\_\_\_\_.
a. mystery image
b. manifest image
c. big picture
d. latent image
d. latent image
164
The principle that explains the formation of the latent image is called:
a. latent image theory
b. quantum speck hypothesis
c. Gurney-Mott hypothesis
d. sensitivity speck postulate
c. Gurney-Mott hypothesis
165
Absorption of a photon causes the release of an electron that is then trapped at an impurity in the silver halide crystal. That in turn makes the spot of the impurity more negative, and attractive to silver is the basis of \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. latent image formation
b. Guthie-Renker hypothesis
c. sensitivity spectra
d. spectral matching
a. latent image formation
166
\_\_\_\_\_\_\_\_\_\_ is a form of image noise.
a. Increased spatial resolution
b. Quantum mechanics
c. Quantum mottle
d. None of the above contribute to image noise
c. Quantum mottle
167
When a lower number of photons are used to create an image, you are going to increase the \_\_\_\_\_\_\_\_\_\_\_\_\_.
a. spectral matching
b. conversion efficiency of the screen
c. spatial resolution
d. quantum mottle
d. quantum mottle
168
Which of the following represents an x-ray interaction with matter?
a. Thomson scatter
b. Characteristic
c. Bremsstrahlung
d. Bohr scatter
a. Thomson scatter
169
The recoil electron is seen with which interaction with matter?
a. Compton
b. Photoelectric
c. Pair production
d. Classical scatter
a. Compton
170
Of the following interactions, which one results in ionization?
a. Photoelectric
b. Compton Pair
c. production
d. All of the above
d. All of the above
171
Which interaction is responsible for producing more subject contrast?
a. Rayleigh scatter
b. Compton scatter
c. Classical scatter
d. Photoelectric
d. Photoelectric
172
Compton interactions occur when:
a. an electron interacts with an inner shell electron
b. an electron interacts with an outer shell electron
c. a photon interacts with an inner shell electron
d. a photon interacts with an outer shell electron
d. a photon interacts with an outer shell electron
173
The probability of a photoelectric interaction increases when:
a. the photon energy is slightly below the k-shell binding energy
b. the photon energy is much greater than the k-shell binding energy
c. the photon energy and the k-shell binding energy match
d. cannot be ejected by x-raysk-shell electrons
c. the photon energy and the k-shell binding energy match
174
How much **photon energy** is required to cause **pair production?**
a. 0.51 MeV
b. 0.75 MeV
c. 1.02 MeV
d. 10.2 MeV
c. 1.02 MeV
175
The **interaction** where the **binding energy of a k-shell electron is overcome by an incident photon** is, what?
a. Characteristic
b. Bremsstrahlung
c. Compton
d. Photoelectric
d. Photoelectric
176
Differential absorption of x-rays by the patient provides the basis of:
a. subject contrast
b. film contrast
c. film density
d. None of the above
a. subject contrast
177
A positron is:
a. an electron with a different name
b. a form of anti-matter
c. a negatively charged electron
d. a photonic version of the electron
b. a form of anti-matter
178
Ejection of an orbital electron by a photon that results in a pair of charged particles is known as:
a. transformation
b. bremsstrahlung
c. ionization
d. photodisintegration
c. ionization
179
Which interaction with matter falls within the diagnostic region?
a. Characteristic
b. Photodisintegration
c. Pair production
d. Compton
d. Compton
180
A recoil electron is seen with which interaction?
a. Characteristic
b. Photoelectric
c. Classical
d. Compton
d. Compton
181
The interaction with matter that is responsible for dose within the patient is:
a. characteristic
b. photoelectric
c. classical scattering
d. Compton
b. photoelectric
182
The factor that controls the quality of the radiation emitted from the tube is \_\_\_\_\_\_\_.
a. mAs
b. KVP
c. FFD
d. SID
b. KVP
183
The **quality of the radiation is altered by adjusting** the ___________ bombarding the anode.
a. number of electrons
b. time the electrons are
c. size of the electrons
d. kinetic energy of the electrons
d. kinetic energy of the electrons
184
Which is TRUE about KVP
a. Increasing KVP decreases film density and increases contrast
b. Increasing KVP increases film density and decreases contrast
c. Decreasing KVP increases film density and decreases contrast
d. Decreasing KVP decreases film density and decreases contrast
b. Increasing KVP increases film density and decreases contrast
"Remember kVp and contrast have inverse relationship"
185
The **part of the x-ray tube that prevents the electrons from spraying all over** the tube is called the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. filament
b. anode
c. anti-cathode
d. focusing cup
d. focusing cup
186
Most modern x-ray tubes utilize which of the following characteristics?
a. rotating anode
b. partially evacuated tube
c. self-rectification
d. All of the above are used in modern tubes
a. rotating anode
187
The **maximum voltage setting for an x-ray technique** is determined by the:
a. mAs
b. FFD
c. kVp
d. OFD
c. kVp
188
The ____________ is on the anode side of the tube?
a. focusing cup
b. target
c. filament
d. collimator
b. target
189
The cloud of electrons produced at the filament is called the:
a. Roentgen cloud
b. focused charge
c. Edison effect
d. Coolidge effect
c. Edison effect
190
The accuracy of a machine's timer may be checked by the __________ test.
a. pinhole camera
b. spin top
c. wire mesh
d. paper clip
b. spin top
191
Which statement **best describes the filament circuit of the x-ray tube?**
a. High voltage; high amperage
b. High voltage; low amperage
c. Low voltage; high amperage
d. Low voltage; low amperage
c. Low voltage; high amperage
192
On which **side of the x-ray field is the apparent focal spot smallest**?
a. Anode
b. Cathode
c. Middle
d. It's the same throughout
a. Anode
193
Which statement regarding controlling (reducing) tube heat is TRUE?
a. Smaller angles dissipate more heat
b. Low kVp and high mAs techniques are preferred
c. Three phase units produce less heat
d. Heat units are determined by kVp x mA
a. Smaller angles dissipate more heat
194
What is the **most common cause of tube failure**?
a. Beam damage
b. Overheating
c. Spark over
d. Filament evaporation
d. Filament evaporation
195
As discussed in class, if a patient's x-rays come out too light, how do you fix it so the image has the correct film blackness?
a. Double the mAs
b. Half the mAs
c. Adjust the kvp up
d. Adjust the kvp down
a. Double the mAs
196
The relationship that mAs has with film density is \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. geometric
b. direct
c. inverse
d. reciprocal
b. direct
197
The current model of the atom used in science today is the _____________ model.
a. Geiger
b. Bohr
c. Roentgen
d. Einstein
b. Bohr
198
Matter is defined as _________________ .
a. anything with weight
b. anything with potential energy
c. kinetic energy at rest
d. anything that occupies space
d. anything that occupies space
199
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ are the basic building blocks of matter.
a. Atoms
b. Photons
c. Electrons
d. Angstroms
a. Atoms
200
Which statement about atoms is TRUE?
a. Electrons are orbited by a nucleus.
b. Atoms are mostly empty space.
c. The nucleus has a neutral charge
d. All of the above are true.
b. Atoms are mostly empty space.
201
The electron shell closest to the nucleus is the ____________ shell.
A
K
M
T
K
202
Electrons may
a. move to higher energy shell w/ emission of energy
b. move to a lower energy shell w/ absorption of energy
c. not move at all
d. move to a higher energy shell w/ absorption of energy
d. move to a higher energy shell w/ absorption of energy
203
The creation of positive and negative ions is called \_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. emission
b. radiation
c. ionization
d. excitation
c. ionization
204
Atoms that exist in an abnormally excited state with an unstable nucleus are \_\_\_\_\_\_\_\_.
a. ionized
b. radioactive
c. energized
d. electromagnetic
b. radioactive
205
The energy of motion is called \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. kinetic energy
b. potential energy
c. electromagnetism
d. chemical energy
a. kinetic energy
206
A **small dense positively charged nucleus with a cloud of negatively charged particles** describes the:
a. Edison effect
b. Bohr model of the atom
c. rectified model of the atom
d. Kassabian hypothesis
b. Bohr model of the atom
207
The **atomic number** of an atom is determined by:
a. number of protons
b. number of neutrons
c. number of protons and neutrons
d. number of protons and electrons
a. number of protons
208
The number of electrons in any given electron shell is governed by the equation 2n2. How many electrons are present in the k-shell of a tungsten atom?
a. 2
b. 8
c. 18
d. 32
a. 2
209
The state of an atom that has an **unstable nucleus that spontaneously emits particles and energy** is called:
a. characteristic production
b. pair production
c. ionization
d. radioactivity
d. radioactivity
210
An object that permits the passage of x-ray through it and produces dark areas on the film is called:
a. radiolucent
b. radiopaque
c. radioactive
d. radiostation
a. radiolucent
211
Which of the following is **FALSE regarding x-rays**?
a. They travel at the speed of light
b. Polyenergetic
c. Can be focused by a lens
d. Cause chemical changes
c. Can be focused by a lens
212
X-rays in the energy range of 30 - 150 keV are used for \_\_\_\_\_\_\_\_\_\_\_.
a. dermatology
b. diagnostic imaging
c. research
d. analysis therapy
b. diagnostic imaging
213
On a T1 weighted MRI image, which of tissues will be bright?
a. Water
b. Cortical bone
c. Fat
d. Cartilage
c. Fat
214
Water based tissues will have more signal (brighter) on which MRI sequence?
a. T1
b. T2
c. Proton density
d. None of the above
b. T2
215
Which of the following methods of imaging does not use ionizing radioation?
a. CT
b. Nuclear medicine
c. Radiography
d. MRI
d. MRI
216
Which method of imaging would be good for detecting multiple areas of suspected bone destruction throughout the body?
a. CT
b. MRI
c. Bone scan
d. Radiography
c. Bone scan
217
Bone scan is a form of imaging that is, \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. sensitive, but not specific
b. specific, but not sensitive
c. sensitive and specific
d. None of the above
a. sensitive, but not specific
218
Manual processing generally takes how much time to complete?
a. 2 minutes
b. 10 minutes
c. 30 minutes
d. 60 minutes
d. 60 minutes
219
The **principle advantage of automatic processing** is what?
a. Increased time
b. Eliminates the variability created by manual processing
c. Less expensive
d. All of the above are advantages
b. Eliminates the variability created by manual processing
220
Most **automatic processors today will process a film in what amount of time**?
a. 45 sec
b. 60 sec
c. 90 sec
d. 120 sec
c. 90 sec
221
What is the **overall purpose of film processing**?
a. Conversion of the latent image into the visible image
b. Conversion of the manifest image into the latent image
c. Reduction of the radiation dose by amplifying the Gurney-Mott hypothesis
d. Depositing the sensitivity speck onto the film emulsion
a. Conversion of the latent image into the visible image
222
Of the following, **which one is a** **step in the processing of a film**?
a. Fixing
b. Heating
c. Running
d. Sequestering
a. Fixing
223
While processing, the **development step performs** which task?
a. Removing excess silver from the emulsion
b. Conversion of the latent image
c. Stops the fixing of the image
d. Hardens the emulsion for processing
b. Conversion of the latent image
224
What is the **optimum temperature for automatic processing**?
a. 55 degrees
b. 70 degrees
c. 95 degrees
d. 120 degrees
c. 95 degrees
225
The **developing solution must** be **periodically** **replenished** for what reason?
a. It becomes explosive
b. It evaporates very quickly
c. It runs over
d. It becomes chemically exhausted
d. It becomes chemically exhausted
226
Of the following, which is **NOT a function of the fixer**?
a. Preserve film image
b. Harden emulsion
c. Remove unexposed silver halide from emulsion
d. Anti-fog agent
d. Anti-fog agent
227
The **clearing time is** defined as the time\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. required for the film to complete processing
b. necessary to convert the latent image
c. needed to remove the unexposed silver crystals from the emulsion
d. it takes for the film to go from the developer into the fixer
c. needed to remove the unexposed silver crystals from the emulsion
228
The **most common type of replenishment used in automatic processing** is \_\_\_\_\_\_\_\_
a. manual
b. flood
c. thermostatic
d. volume
d. volume
229
Automatic processors that use cold tap water to wash their films off use which type of temperature control system?
a. Thermostatically controlled
b. Volume controlled
c. Water controlled
d. Flood controlled
a. Thermostatically controlled
230
According to federal guidelines silver content is liquid waste from your processor cannot exceed \_\_\_\_\_\_\_\_\_\_\_\_\_.
a. 1 ppm
b. 5 ppm
c. 10 ppm
d. 15 ppm
b. 5 ppm
231
Metallic replacement is a method of ?
a. Development
b. Scatter control
c. Developer replenishment
d. Silver reclamation
d. Silver reclamation
232
What would happen if fixer were added to the developer tank of the processor?
a. Nothing
b. The film would get caught in the processor
c. The developer would neutralize the fixer and the unexposed silver would not be removed
d. The fixer would neutralize the developer and the film would not be developed
d. The fixer would neutralize the developer and the film would not be developed
233
\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is part of the developer.
a. Sodium thiosulfate
b. Potassium alum
c. Phenidone
d. Methidone
c. Phenidone
234
The **form of x-ray production that is dependent on the k-shell electron binding energy** is \_\_\_\_\_\_\_\_\_\_\_.
a. photoelectric
b. characteristic
c. bremsstrahlung
d. Rayleigh
b. characteristic
235
The **form of radiation production that results from an electron giving up its energy as it nears the nucleus**:
a. depends on k-shell binding energies for most of its x-ray production
b. produces about 20% of the x-ray beam
c. also occurs within the intensifying screen
d. is responsible for the heterogeneity of the beam
d. is responsible for the heterogeneity of the beam
236
To produce a characteristic x-ray the kVp must be set to at least, what?
a. 20 kVp
b. 50 kVp
c. 70 kVp
d. 80 kVp
c. 70 kVp
237
The recommended **lead** **thickness for protective aprons** in the radiography suite is _____ mm Pb.
a. 0.001
b. 0.25
c. 0.15
d. 0.5
d. 0.5
238
To **protect your patients, your collimator must be within** _______ of the indicated field.
a. 1%
b. 2%
c. 5%
d. 10%
b. 2%
239
In order to maintain safety in the radiography suite, you must exercise the principles of protection. **Which of the following is NOT considered a method of radiation protection**?
a. Short exposure time
b. Large distance between the source and patient
c. Shielding
d. Large collimation field
d. Large collimation field
240
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_was the first reported radiation fatality in the U.S.
a. Mirhan Kassabian
b. Clarence Dally
c. Thomas Edison
d. Wilhelm Roentgen
b. Clarence Dally
241
The doctor that documented his own radiation injuries so that the information could be used after his death was, who?
a. Mirhan Kassabian
b. Clarence Dally
c. Thomas Edison
d. Wilhelm Roentgen
a. Mirhan Kassabian
242
The **amount of radiation required to produce a certain degree of skin erythema** is known as:
a. MeV
b. RAD
c. SED
d. Sievert
c. SED
243
The unit of radiation measurement that measures the amount of ionization left behind by the radiation is the \_\_\_\_\_\_\_\_\_\_\_\_\_.
a. RAD
b. REM
c. Roentgen
d. Sievert
c. Roentgen
244
The SI unit of occupational dose is the:
a. REM
b. RAD
c. Gray
d. Sievert
d. Sievert
245
There are ___________ RAD's in a Gray.
a. 1
b. 10
c. 100
d. 1000
c. 100
246
One Sievert is equal to \_\_\_\_\_\_\_\_\_\_.
a. 10 Grays
b. 100 RADs
c. 100 REMs
d. 100 Roentgens
c. 100 REMs
247
Multiplying the amount of absorbed dose by a quality factor gives the \_\_\_\_\_\_\_\_.
a. Dose equivalent
b. Linear energy transfer
c. Energy per kilogram of matter
d. None of the above
a. Dose equivalent
248
Radiation induced GI distress can be produced with how much dose?
50 REM
100 REM
150 REM
250 REM
150 REM
249
The amount of radiation that the average person receives from background sources is \_\_\_\_\_\_\_\_\_\_\_mR/year.
a. 10
b. 50
c. 120
d. 180
c. 120 mR/year
250
\_\_\_\_\_\_\_\_\_\_\_\_\_ is a type of natural radiation.
a. Organic
b. Terrestrial
c. Diagnostic
d. Coherent
b. Terrestrial
251
The general public is limited to ___________ of radiation, not including medical exams.
a. 0.5 REM/year
b. 1.0 REM/year
c. 5.0 REM/year
d. 0.5 Sieverts/year
a. 0.5 REM/year
252
A radiological technology student in your office who is 17 years old is allowed how much radiation exposure per year?
a. 0.001 REM
b. 0.01 REM
c. 0.1 REM
d. 1.0 REM
a. 0.001 REM
253
The maximum amount of occupational radiation that a person may receive during their lifetime is, what?
a. 0.5 per year x their age / 2
b. 1/10 of a REM per years of working in radiation
c. Total dose of medical exams + total occupational exposure / age
d. Should not exceed their age in REMs
d. Should not exceed their age in REMs
254
Which of the following exams is responsible for a significant amount of dosage from medical exams?
a. Lumbar spine
b. Chest
c. Skull
d. Extremities
a. Lumbar spine
255
As kvp increases \_\_\_\_\_\_\_\_\_\_\_\_\_.
a. compton radiation scatters more forward
b. photoelectric absorption prevents scatter formation
c. photons scatter more back towards the source
d. none of the above
a. compton radiation scatters more forward
256
Photons that interact with the patient and change direction to go on to strike the film are called, what?
a. Bucky fog
b. compton scatter
c. orbital decay
d. pair production
b. compton scatter
257
Which of the following **increases the amount of scatter produced** in a patient?
a. Decreasing kvp
b. Increased patient thickness
c. Compressing the patient
d. Decreasing the x-ray field size
b. Increased patient thickness
258
How much of the film blackness do x-rays expose by themselves?
a. 1%
b. 20%
c. 50%
d. 90%
a. 1%
259
Which effect takes place in the screen to convert x-rays into visible light?
a. Bremsstrahlung
b. Compton
c. Conduction band theory
d. Rayleigh
c. Conduction band theory
260
Which of the following statements is TRUE?
a. Intensifying screens improve image quality substantially
b. Screens dramatically decrease patient dose
c. Intensifying screens are made of copper and iodine
d. Intensifying screens invented by Clarence Dally
b. Screens dramatically decrease patient dose
261
**Modern intensifying screens use which element** as their active component?
a. Gadolinium
b. Iridium
c. Helium
d. Rhenium
a. Gadolinium
262
\_\_\_\_\_\_\_\_\_\_\_\_\_ is the **light producing layer of the intensifying screen.**
a. The base
b. The reflecting layer
c. The protective layer
d. The phosphor layer
d. The phosphor layer
263
If **light is emitted by the intensifying screen slower than 10-8 seconds**, what is **this effect** called?
a. Phosphorescence
b. Conduction band instability
c. Edison effect
d. Afterglow
d. Afterglow
264
The **process by which light is emitted by an intensifying screen** is called \_\_\_\_\_\_\_\_\_.
a. fluorescence
b. phosphorescence
c. light bringing
a. fluorescence
265
The **number that indicates the relative sensitivity of a screen to x-rays** is the:
a. luminescence
b. intensification factor
c. speed
d. neediness
c. speed
266
**Calcium tungstate i**s given the **standard speed** number of \_\_\_\_\_\_\_\_\_\_\_.
a. 100 b. 300 c. 800 d. 1000
a. 100
267
An intensifying screen that decreases the exposure of a given radiographic technique by 25 times over a non-screen technique with the same film density has a(n) __________ of \_\_\_\_\_\_\_\_\_\_\_.
a. speed; 100
b. intensification factor; 25
c. filtration; 5
d. pair production; 1/25
b. intensification factor; 25
268
The increase in beam absorption as photon energies match the k-shell binding energy is called:
a. k-edge
b. k-match
c. photoelectric effect
d. k-charge effect
a. k-edge
269
An **incident photon is captured by a crystal in an intensifying screen and emits light to expose film**, this is an example of:
a. Photodisintigration
b. Conduction band theory
c. Gurney-Mott hypothesis
d. None of the above
b. Conduction band theory
270
Producing a large amount of light per x-ray absorption is
a. fluorescence
b. luminescence
c. conversion efficiency
d. spectral matching
c. conversion efficiency
271
The **active layer of an intensifying screen** is the
a. phosphor layer
b. base
c. reflective layer
d. None of these are active
a. phosphor layer
272
Most screens are only about ______________ efficient in converting x-ray to light.
a. 1%
b. 5%
c. 15%
d. 40%
c. 15%
273
What can be done to **determine the presence of poor screen contact**?
a. Spin top test
b. Hinge test
c. Screen clean test
d. Wire mesh test
d. Wire mesh test
274
What is the difference between fluorescence and phosphorescence?
a. Fluorescence is slower than 10-8 seconds
b. Phosphorescence is faster than 10-8 seconds
c. Fluorescence has an afterglow
d. None of the above
d. None of the above
275
What substance is used as the standard 100 speed in intensifying screens?
a. Gadolinium
b. Calcium tungstate
c. Yttrium
d. Zinc sulfide
b. Calcium tungstate
276
The ___ is the **point of increased absorption due to the matching of binding** and **photon energies.**
a. k-shell
b. k-edge
c. k-bar
d. k-band
b. k-edge
277
The **space charge effect at the filament happens with**, what?
The amount of electrons surrounding the filament don't leave enough room for new ones to leave the filament
The large amount of electrons createing a very negative charge and keeps new electrons from leaving the filament
Machines operating above 100 mA d.
None of the above are correct
The large amount of electrons createing a very negative charge and keeps new electrons from leaving the filament
278
In 1895 Roentgen was working in his lab, when he noticed a **plate began to emit light, what was the plate coated with**?
a. Methyl methacrylate
b. Zinc
c. Calcium tungstate
d. Barium platinocyanide
d. Barium platinocyanide
279
**_PART I_**
A 35 y.o. male patient comes to your office with a history of low back pain. You decide to x-ray his lumbar spine. In the AP direction he measures 27 cm and laterally, 39 cm. The Total Correction Factor (TCF) in your suite for regular cassettes is -4. What is the mAs for an AP lumbar spine view at 80 kVp (40 FFD with bucky (12:1 grid) technique)?
A. 15
B. 25
C. 50
D. 75
**_PART II_**
Using the information from the last question, what is the exposure time for a lateral lumbar spine view at 90 kVp using a 200 mA time station?
a. 1/5 sec
b. 1/2 sec
c. 3/10 sec
d. 3/4 sec
**_PART I_**
* 50
**_PART II_**
* 1/2 sec
280
To examine a patient for pneumonia, you decide to shoot a PA chest x-ray. The patient is a body builder and he measures 24 cm in the PA direction. What is the mAs for this shot at 72" in the grid at 120 kVp, with a TCF of -5 1/2 for your chest cassette in this room?
a. 1.00
b. 1.5
c. 3.3
d. 7
b. 1.5
281
Transformers require ____________ to operate. a. direct current (DC) b. alternating current (AC) c. rectifiers d. diodes
b. alternating current
282
A **transformer with a turn ratio greater than 1** is a ___________ transformer.
a. step-up
b. step-down
c. auto
d. rectifying
a. step-up
283
Alternating current passed through wire looped around a metal core will induce a(n) ___________ in the metal core.
a. moving electrical field
b. static electrical charge
c. ionization
d. alternating magnetic field
d. alternating magnetic field
284
A **step-down transformer** would have:
a. a turn ratio of 0.5
b. a turn ratio of 1
c. a turn ratio of 100
d. none of the above
a. a turn ratio of 0.5
285
In order to change electrical wall current into something an x-ray tube can use, which piece of equipment is utilized?
a. LED
b. LCD
c. Tube stand
d. Transformer
d. Transformer
286
**Electrons are liberated from the filament** by which process?
a. Thermoionic emission
b. Thermal ignition
c. Thermal ejection
d. Thermoionic eversion
a. Thermoionic emission
287
The **cloud of electrons created around the filament when the low voltage current is activated** is called, what?
a. The Roentgen cloud
b. Space-charge
c. Ionic cloud
d. None of the above
b. Space-charge
288
The target material of the anode is made of \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. Copper
b. Lead
c. Tungsten
d. Uranium
c. Tungsten
289
The part of the cathode that keeps electrons from flying all over the tube is \_\_\_\_\_\_\_\_.
a. filament
b. target
c. focusing cup
d. stator coil
c. focusing cup
290
Modern x-ray tubes used in chiropractic offices use which of the following:
a. stationary anode
b. rotating anode
c. rotating cathode
d. glass focusing cup
b. rotating anode
291
The **main advantage to a rotating anode** is:
a. greater heat capacity
b. lower melting point
c. electrons spin to produce more focused x-rays
d. none of the above are advantageous
a. greater heat capacity
292
X-rays exit the tube through the
a. tube window b. cathode c. stator d. anode
b. window
293
What is the **most common cause for x-ray tube failure**?
a. Spark over
b. Heel effect
c. Filament evaporation
d. Heat convection
c. Filament evaporation
294
What **speed film/cassette combination works best for general purpose spinal radiography**?
a. 100
b. 200
c. 400
d. 800
c. 400
295
What of the following aids in obtaining optimal AP thoracic x-rays?
a. Open collimation
b. Aluminum wedge filter
c. Inherent filtration
d. Ion pair production
b. Aluminum wedge filter
296
What **patient information is required on the ID stamper?**
a. Name, Age, Sex, Date of Service
b. Name, Sex, Ethnicity, Date of Service
c. Name, Age, Sex, Date of Birth
d. Name, Date of Birth, Sex
a. Name, Age, Sex, Date of Service
297
Which of the following is **NOT a factor in causing safelight fog**?
a. Filter color
b. Bulb wattage
c. Time under the safelight
d. Film type
d. Film type
298
The deceleration of electrons to produce x-rays is called \_\_\_\_\_\_\_\_\_\_\_\_.
a. characteristic
b. compton
c. bremsstrahlung
d. photoelectric
c. bremsstrahlung
299
The majority of x-rays produced in the anode result from which process?
a. Bremsstrahlung
b. Characteristic
c. Pair Production
d. Photoelectric
a. Bremsstrahlung
300
What percentage of x-rays produced at the anode result from the displacement of a k-shell electron?
a. 20% b. 45% c. 60% d. 90%
a. 20%
301
At the anode, an incident electron ejects a k-shell electron from its orbit. When is an x-ray is emitted?
a. When another electron comes along to take its place
b. When an outer shell electron drops in to fill the vacancy
c. When the nucleus ejects a positron to fill the vacancy
d. When the incident has the energy to 0.51 MeV
b. When an outer shell electron drops in to fill the vacancy
302
What is the binding energy of a Tungsten (W) k-shell electron?
a. 30.2 keV
b. 57.4 keV
c. 69.5 keV
d. 75.3 keV
c. 69.5 keV
303
Bremsstrahlung is also known as:
a. braking radiation
b. characteristic radiation
c. sonic radiation
d. photoradiation
a. braking radiation
304
Of Bremsstrahlung radiation production, which is TRUE?
a. The lower the atomic number of the anode, the higher the contrast
b. The higher the atomic number of the target the higher the energy x-ray produced
c. Gives distinct spikes of radiation production
d. All of the above are true
b. The higher the atomic number of the target the higher the energy x-ray produced
305
Characteristic radiation production produces
a. lower energy radiation with higher target atomic numbers
b. radiation energies that are independent of the target material used
c. the majority of x-rays below 80 kvp
d. radiation energies that are specific to differences between electron orbits
d. radiation energies that are specific to differences between electron orbits
306
We usually measure the energy of x-rays in \_\_\_\_\_\_\_\_\_\_\_\_.
a. wavelengths
b. frequencies
c. Planck constants
d. electron volts
d. electron volts
307
An object that permits the passage of x-rays is said to be \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
a. radiolucent
b. radiopaque
c. radiosensitive
d. radiostationary
a. radiolucent
308
The white area of a radiograph results from x-rays encountering a ___________ area.
a. radiolucent
b. radiopaque
c. radiosensitive
d. radiostationary
b. radiopaque
309
Which of the following is **_FALSE regarding x-rays_**?
a. They are electrically neutral.
b. They cannot be focused.
c. They are monoenergetic.
d. They travel at the speed of light.
c. They are monoenergetic.
310
Identify "A" Window Glass tube Stator coil Anode Identify "B" Glass tube Transformer Stator coil Anode Identify "C" Anode Cathode Focusing Cup Stator coil Identify "D" Cathode Stator Coil Filament Exit window Identify "E" Target Stator coil Filament Transformer Identify "F" Filament Focusing cup Stator coil Target
A
311
The type of voltage rectification with the LEAST amount of ripple is \_\_\_\_\_\_\_\_\_.
a. single phase fully rectified
b. self rectified
c. three phase - 6 pulse
d. High frequency
d. High frequency (voltage ripple of 1%)
* single phase voltage ripple - 100%
* 3 phase 6 pulse voltage ripple - 14%
* 3 phase 12 pulse voltage ripple - 4%
312
The NCRP limits occupational exposure to ___________ per year.
5 Grays
10 RADs
5 REMs
500 Sieverts
5 REMs
313
Intensifying screen efficiency is approximately:
1%
20%
50%
75%
20%
