Final Exam Flashcards
(139 cards)
1
Q
What is the standard unit for radiation intensity?
A
Roentgen (R)
2
Q
What are the cardinal rules?
A
- Time
- Distance
- Shielding
3
Q
What is the purpose of tube house?
A
To…
- shield and cool x-ray tube
- to prevent excessive radiation exposure
4
Q
What determines the mAs of an atom?
A
The combination of protons and neutrons (Atomic mass #)
5
Q
All group atoms have the same # of ____?
A
Same # of electrons on the outermost shell
6
Q
Define ionic bonding
A
When one atom either gives up or gain an electron causing the attraction of opposing charges
7
Q
What are the 3 components of an atom?
A
- protons
- neutrons
- electrons
8
Q
When were x-rays discovered?
A
November 8th, 1895
9
Q
What is the purpose of permanent equipment?
A
To provide stability and reliability for routine imaging
10
Q
What is the SI unit for mass?
A
Kilogram
11
Q
What is the relationship between frequency and wavelength?
A
Indirectly proportional
12
Q
Why study the atom?
A
Because interactions in the x-ray tube, and interactions with a human body all happen at an atomic level
13
Q
Upright exams are done where in the examination room?
A
On the wall Bucky
14
Q
What is the outermost shell letter?
A
Shell letter Q
15
Q
Define fundamental quantities?
A
They are independent physical quantities that serve as the foundation for measuring other quantities such as … length, mass, time
16
Q
What is the relationship between frequency and wavelength?
A
Indirectly proportional
17
Q
Inverse square law question
A
18
Q
Define isobars
A
Different # of protons but same # of protons and neutrons
19
Q
What is the relationship between frequency and wavelength?
A
Indirectly proportional
20
Q
Inverse square law question
A
21
Q
What is the unit for occupational dose?
A
Rad - Gray
22
Q
What is the unit for occupational dose?
A
Rad - Gray
23
Q
Define wave particle duality
A
Exhibits properties of both particle and a wave depending on its energy and environment
24
Q
Define inverse square law
A
25
What is not considered part of the electromagnetic spectrum?
Not considered is …
- sound waves
26
What is the SI unit for patient dose?
Gray
27
What is the function of the collimator?
To restrict and shape a beam to a specific area to minimize unnecessary exposure
28
What did Roentgen contribute to the medical field?
He discovered x-rays
29
Define radioactive element?
Is a radioactive material that gives off a form of energy that travels in waves or particles called radiation
30
What is the purpose of mAs and kVp?
mA controls the quantity if x-rays produced while kVp controls the quality of the x-ray beam
31
What is the advantage of mobile equipment?
It can be used in many rooms like ER’s, surgical rooms, ICU’s etc.
32
What is the closet shell in the nucleus?
K shell
33
Define molecule
Made up of two or more atoms
34
Define inverse square law
35
Define ionization
The process in which an atom gaining or losing electrons
36
What is the SI unit of different types of radiation?
Sievert
37
The nucleus contains what?
Protons and neutrons
38
Radio waves are used in..?
MRI
39
Who established the code of ethics?
American Society of Radiology Technologists (ASRT)
40
How are x-rays and gamma rays different?
They ionize
41
Define inertia
the property of an object with mass that resists a change in its state of motion.
42
Helium contains what particles?
2 protons
2 neutrons
2 orbiting electrons
43
Lead shutters are part of?
Collimator
44
Define potential energy
is energy in a stored state
45
Which type has the longest wavelength?
Radio waves
46
What are the cardinal rules?
- Time
- Distance
- Shielding
47
Define ALARA
As Low As Reasonably Achievable
48
Define wavelength
is the distance from one peak to another
49
Define AC
Alternating Current
50
What is the anode heel affect?
the “heel” of the target is partially placed in the path of the x-ray beam produced, causing absorption and reduced intensity of the beam on the anode side
51
Define line focus principle
a large actual focal spot is maintained to spread heat load and create a small effective focal spot to improve image detail
52
Define tube current
the amount of electric current flowing through the X-ray tube
53
What are the functions of a step down transformer?
- reduce kilivoltage to voltage
54
What is needed for the flow of electrons on a conductor?
Voltage and an unbroken circuit
55
Define line focus principle
a large actual focal spot is maintained to spread heat load and create a small effective focal spot to improve image detail
56
Pathways needs to be ____ for flow of electricity
Closed
57
What is the advantage of small focal spot?
Improve sharpness of the image
58
What are the different parts of the circuit?
- primary circuit
- secondary circuit
- filament circuit
59
Volts measures what?
Electric potential difference
60
Like poles ____, opposites ____
- repel
- attract
61
Define motor
Important part to facilitate efficient heat dissapation
62
What material lines the tube housing?
Lead
63
Selecting focal spot means?
Selecting which filament heats up
64
Define resistor
Controls the flow of electrons
65
Define autotransformer
It’s device that controls voltage adjustment
66
Define semi conductor
Material with electrical conductivity between that of a conductor and an insulator
67
What is the last step of x-ray production?
- Filaments heat up forming electron cloud
- electrons are sent towards anode target
- once target is hit, energy is released in the form of x-ray photons
- then x-rays are produced
68
Define molybdenum
used as the disc base and core because it has a low thermal conductivity and it is a light but strong alloy
69
What percentage of energy is x-rays?
1% x-rays, 99% heat
70
Define ripple
the variation in the voltage output of an X-ray generator
71
Purpose of the tube housing?
To…
- shield and cool x-ray tube
- to prevent excessive radiation exposure
72
Define rectification
The process of converting alternating current to direct current
73
Put x-ray production events in order…
Filaments heat up forming electron cloud
- electrons are sent towards anode target
- once target is hit, energy is released in the form of x-ray photons
- then x-rays are produced
74
Define auto transformer
It’s device that controls voltage adjustment
75
Define anode heel affect
the “heel” of the target is partially placed in the path of the x-ray beam produced, causing absorption and reduced intensity of the beam on the anode side
76
What is the location of filaments
Filament circuit
77
Advantage of rotating anode
Spreads heat
78
Location of timer switch?
Primary circuit
79
Parts of the anode includes …?
- copper shaft
- Molybdenum disc base and core
- Tungsten used due to very high melting point
80
Define ohm’s law
The potential difference (voltage) across the total circuit or any part of that circuit is equal to the current
81
Define ferromagnetic
are strongly attracted to magnetic materials
82
Location of the stator?
In a rotating anode
83
Define magnetism
The ability of a material to attract iron, cobalt, or nickel
84
Define ripple
the variation in the voltage output of an X-ray generator
85
Define line compensator
a device usually wired to the autotransformer that automatically adjusts the power supplied to the x-ray machine to 220 volts
86
Why is tungsten used?
- Tungsten used due to very high melting point
87
What is used to cool x-ray tube?
Oil baths and cooling fans
88
Anode is made up of ?
A rotating tungsten-coated molybdenum disc mounted on a copper shaft with a molybdenum core
89
What is the Purpose of the focusing cup?
Focus target to anode
90
Define AC
Alternating current
91
What is used to cool x-ray tube?
Oil baths and cooling fans
92
Pic of photoelectric interaction
93
How to minimize occupational exposure?
Apply cardinal rules
94
Which interaction is the source of occupational exposure?
Compton scattering
95
Relationship between filtration and quantity?
Inversely proportional
96
When is a characteristic photon produced?
When an outer shell fills in vacancy places
97
If kVp is 75 … what is the energy range?
0-75 KeV range
98
Compton results in …?
results in the loss of an electron and ionization of the absorbing atom
99
Relationship between distance and quantity?
Inversely proportional
100
When do you get a characteristic photon?
When an outer shell electron fills an inner shell vacancy
101
Define x-ray quantity
# of x-ray photons
102
Pic of Brems
103
What happens to the emissions spectrum when we go from high frequency to single phase generator?
The emission spectrum shifts
104
Secondary photon is produced by … ?
Compton effect
105
Define cascade effect
where an initial action or event triggers a series of ripples
106
Relationship between quantity and mAs is …?
Directly proportional
107
Change in the x - axis is change in the …?
Increase in kVp
108
Define hard beam?
more penetrating and less likely to be absorbed by tissues, resulting in a higher-quality image
109
Picture … graph of increase in mA
110
What is needed to produce x-ray image?
111
What is the primary source of occupational exposure?
Compton scattering
112
Define x-ray quantity
# of x-ray photons
113
Define cascade
where an initial action or event triggers a series of ripples
114
Emission spectrum graphs what?
the pattern of lines seen when light from a substance is separated out into its different wavelengths
115
Define classical scattering photons
incident x-ray photon interacts with an orbital electron of a tissue atom and changes direction
116
Photoelectric interactions occur on ___?
The bone
117
What happen during photoelectric interactions?
The photo is completely absorbed and its energy is transferred to an electron that is removed from the electron cloud
118
Transmitted x-rays appear ….?
Light shade of gray
119
Define Compton scattering
An incident x-ray photon enters a tissue atom, interacts with an orbital electron and removes it from its shell. The incident photon loses up to one third of its energy and is usually deflected in a new direction.
120
Which factors change appearance of x-ray image?
Focal spot
121
Relationship is between mA and quantity
Directly proportional
122
Define transmitted radiation
the passage of electromagnetic radiation through a medium without significant absorption or reflection.
123
How is quality measured?
HVL ( Half Value Layer)
124
Air is considered radiolucent or radioapauge?
Radiolucent
125
Picture of Compton interaction
126
Graph of increase in kVp
127
Inverse square law question
128
Define transmitted radiation
the passage of electromagnetic radiation through a medium without significant absorption or reflection.
129
Relationship between quality and kVp
Directly proportional
130
Does Pair production happen in x-ray diagnostic range?
No
131
How to minimize radiation exposure?
Apply cardinal rules
132
Inverse square law question
133
What percentage is x-rays?
1% x-rays, 99% heat
134
Inverse square law question
135
Inverse square law question
136
Energy range of Compton is?
20-40 keV
137
Radiation interaction with bone appears as?
Light gray
138
Energy range of Compton is?
139
Energy range of Compton is?
20-40 keV
