Chapters 2, 3, and 5 Flashcards
(246 cards)
1
Q
Define Atom
A
- means indivisible
- the basic building block of matter
2
Q
What was Bohr’s theory?
A
an atom consisted of 3 fundamental particles: protons, neutrons, and electrons
3
Q
define nucleus
A
- made up of protons and neutrons
- also called nucleons
- electrons surround the nucleus in defined energy levels (shells)
4
Q
define a proton
A
- positively charged ion
5
Q
define a neutron
A
- neutral charged or no electrical charge
6
Q
define an electron
A
- negatively charged ion
- surrounds/orbits the atom
- low mass
- moves at a rapid pace = lots of kinetic energy
7
Q
define ionization
A
- losing or gaining an electron
8
Q
define anion
A
- negative ion
- when an atom gains an electron
- have a higher negative charge
9
Q
define a cation
A
- positive ion
- when an atom loses an electron
- has a higher positive charge
10
Q
define atomic charge
A
- Within each atom, each proton has one unit of positive charge, each electron has one unit of negative charge, and neutrons have no charge.
- aka fundamental particles
11
Q
define binding energy
A
- a strong nuclear force that holds the nucleus together.
- Holds the protons and neutrons together in the nucleus.
- Also a measure of the amount of energy necessary to split an atom.
12
Q
what are the 2 different types of binding energy?
A
- Nuclear binding energy
- Electron binding energy
- both are key determinate of x-ray production
13
Q
define Nuclear binding energy
A
- if a particle strikes the nucleus with energy equal to the nucleus’s binding energy, it could break apart
14
Q
define electron binding energy
A
- how electrons are held in their orbits.
- This energy depends on how close the electron is to the nucleus and how many protons are in the atom.
- energy decreases with each subsequent shell
15
Q
What is the inner shell called?
A
- K shell
- has the strongest electron binding energy (since its closer to the nucleus)
16
Q
What are the names of the other shells?
A
- K, L, M, N, O, P, etc
17
Q
how many electrons does the K shell hold?
A
2 electrons
18
Q
What formula is used to determine how much electrons a shell can carry ?
A
- 2n^2
- “n” represents the number of shells
- Ex.) Shell K is 1, Shell L is 2, and so forth
19
Q
define mass defect
A
represents the energy necessary to hold the nucleus together
20
Q
What are the 2 atomic reactions in the x-ray tube that produces x-rays?
A
- characteristic and bremsstrahlung
21
Q
define characteristic
A
- the removal of orbital electrons from atoms.
- depends on electron-binding energy
22
Q
define Bremsstrahlung
A
- involves attraction to the nucleus of the atom
- depends on Nuclear binding energy
23
Q
define electron shells
A
- a sphere around a nucleus
- defined energy levels, each at a different distance from the nucleus
24
Q
how many shells can fit in the outer shells?
A
- 8 electrons
25
define atomic number
- the number of protons it contains in the nucleus
26
define atomic mass number
- number of protons and neutrons an atom has in the nucleus
27
define elements
- the simplest form of substances that compose matter
- each is made up of one unique type of atom
- Ex.) O, N, He, Fe
28
define molecule
- two or more atoms bonded
29
define chemical compounds
- combinations of elements bonded together
- H2O, CO2
30
define chemical symbol
- abbreviation of the element
- H is for hydrogen
31
when looking at an element (in the periodic table), what is the superscript that is above the chemical symbol?
- atomic mass number
32
when looking at an element (in the periodic table), what is the superscript that is below the chemical symbol?
- atomic number
33
define isotope
- elements whose atoms have the same number of protons but a different number of neutrons
34
define isotone
- an element with the same number of neutrons, but different number of protons
35
define isobar
- elements that have a a different number of protons, but the same total number of of protons and neutrons (atomic mass number)
36
define isomer
- elements with the same number of protons and neutrons but with different amounts of energy within their nuclei
37
what would be an example of isotopes?
1/1 H and 2/1 H
38
what would be an example of isotones?
131/23 I and 132/54 Xe
39
what would be an example of isobar?
7/3 Li and 7/4 Be
40
what would be an example of an isomer?
99m Tc
41
define the periodic table
- a table that consists of multiple elements
- consists of periods and columns
- all are different types of metals
42
what is a period on a periodic table?
- top to bottom
- same number of electron shells
- increases as you move from top to bottom
- become larger and more complex
43
what is a group on a periodic table?
- left to right
- same number of electrons in the outer shell
- amount increases as you move from left to right
44
define compound
- a molecule that contains at least two different elements
45
define ionic bonding
- attraction of opposite charges
- one of the atoms gives up an electron and the other takes the extra electron
- the difference in their electrical charge attracts and bonds the two together
46
define covalent bonding
- two atoms sharing electrons
- outermost electron from one atom begins to orbit the nucleus of another adjacent atom
47
What does the size of an atom determine?
- the more large and complex an atom is, they have a higher chance for interactions
- the smaller and simple an atom is, they have a lesser chance of interaction
48
define an alpha particle
- made up of 2 protons and 2 neutrons
- have a positive charge
49
3. How many protons does 131/53 I have?
a. 131
b. 53
c. 78
d. 184
b. 53
50
4. How many nucleons are in (39/19 K)?
a. 39
b. 19
c. 20
d. 58
a. 39
51
5. 132/54 Xe and 131/53 I are:
a. isomers.
b. isotopes.
c. isobars.
d. Isotones.
d. Isotones.
52
6. 130/53 I and 131/53 I are:
a. isotopes.
b. isobars.
c. isotones.
d. Isomers.
a. isotopes.
53
7. What is the maximum number of electrons that will occupy the outermost shell of an atom?
a. 2
b. 8
c. 18
d. 32
b. 8
54
8. The maximum number of electrons that can occupy the P shell is:
a. 8.
b. 32.
c. 72.
d. 98.
c. 72.
55
9. Atoms that bind together because of their opposite charges form:
a. covalent bonds.
b. convalescent bonds.
c. ionic bonds.
d. nonionic bonds.
c. ionic bonds.
56
10. The horizontal periods of the periodic table contain elements with:
a. the same number of electron shells.
b. the same number of electrons.
c. the same chemical properties.
d. the same number of protons.
a. the same number of electron shells.
57
1. Which of the following is considered a nucleon?
a. proton
b. electron
c. alpha particle
d. beta particle
a. proton
58
2. What is the maximum number of electrons permitted in the M shell?
a. 8
b. 18
c. 32
d. 50
b. 18
59
define electromagnetic radiation
- no mass
- carries energy in waves as electric and magnetic disturbances in space
- travels in the speed of light (3 x 10^8)
60
define the electromagnetic spectrum
- ordering or grouping the different electromagnetic radiations
- all waves have the same velocity ( 3 x 10^8)
- vary on energy, wavelength, and frequency
61
What is are the levels of the electromagnetic spectrum from lowest energy to greatest?
1. Radiowaves
2. Microwaves
3. Infrared light
4. visible light
5. ultraviolet light
6. x-rays
7. gamma rays
62
define the nature of electromagnetic radiation
- electric and magnetic disturbances traveling through space
- They all have the same velocity (3 x 10^8)
- vary only in their energy, wavelength, and frequency
63
What is the wavelength (m) and frequency (HZ) for radiowaves?
Wavelength (m): >1 x 10^-1
Frequency (Hz): >3 x 10^9
64
What is the wavelength (m) and frequency (HZ) for microwaves?
Wavelength (m): 1 x 10^-1 - 1 x 10^-3
Frequency (Hz): 3 x 10^9 - 3 x 10^11
65
What is the wavelength (m) and frequency (HZ) for Infrared Light (IR)?
Wavelength (m): 1 x 10^-3 - 7 x 10^-7
Frequency (Hz): 3 x 10^11 - 4 x 10^14
66
What is the wavelength (m) and frequency (HZ) for Visible light?
Wavelength (m): 7 x 10^-7 - 4 x 10^-7
Frequency (Hz): 4 x 10^14 - 8 x 10^14
67
What is the wavelength (m) and frequency (HZ) for Ultraviolet?
Wavelength (m): 4 x 10^-7 - 1 x 10^-8
Frequency (Hz): 8 x 10^14 - 3 x 10^17
68
What is the wavelength (m) and frequency (HZ) for X-rays?
Wavelength (m): 1 x 10^-8 - 1 x 10^-13
Frequency (Hz): 3 x 10^17 - 3 x 10^19
69
What is the wavelength (m) and frequency (HZ) for Gamma rays?
Wavelength (m): <10^-11
Frequency (Hz): >3 x 10^17
70
define electromagnetic radiation
- form of energy that originates from the atom
- emitted when changes in atoms occur
- can exist apart from matter and can travel through a vacuum
- it's pure energy
- does not require a medium to travel
71
what is the formula when calculating electromagnetic radiation?
- E=hf
- E is energy
- h is Planck's constant
- f is frequency
72
what's the difference between an electromagnetic radiation vs. a mechanical radiation?
- electromagnetic does not need a medium to travel
- mechanical requires a medium in order to travel to other locations
73
define amplitude
- maximum height of a wave
74
define wavelength
- measure of the distance from the peak of one wave to the other
75
define frequency
- number of waves that pass a given point per second
76
what is the relationship between wavelength and frequency?
- inverse
- the longer the wavelength, the shorter the frequency
77
what is the unit to measure frequency?
- Hertz
- One hertz is defined as one cycle per second
78
What is the formula to calculate wavelength and frequency?
- c = fλ
- C is the constant of speed of light (3 x 10^8)
- f is frequency
- λ is wavelength
79
how can electromagnetic radiation be characterized when it interacts with matter?
- if its a high energy photon (x-rays and gamma rays), it's characterized as a particle
- if its a low energy photon (radiowaves and microwaves) it's characterized as a wave
80
define inverse square law in radiation
- the intensity of radiation diminishes by the square of the distance from the source
- used to calculate the change in the intensity (quantity) of radiation reaching the image receptor with changes in distance.
81
define wave particle duality
- how electromagnetic radiation exhibits properties of both a particle and a wave, depending on its energy and environment.
82
What are the characteristics of x-rays and gamma rays?
- highest-energy members of the electromagnetic spectrum
- can burn the skin
- the ability to ionize matter
- dangerous in general and harmful to the patient if misused
- can damage molecules and deoxyribonucleic acid (DNA) and cause chemical changes in cells
83
What's the difference between an x-ray and a gamma ray?
- source of energy
84
Where do gamma rays originate?
- nuclei of atoms
85
where do x-rays originate?
- interactions between electrons and atoms
86
define Radiowaves
- low end of the energy spectrum
- commonly used in MRI
- radiowaves do not ionize atoms.
87
define microwaves
- transmit cell phone signals and heat food.
- do not ionize atoms
88
define infrared light
- low-energy, electromagnetic radiation just above microwaves
- “beam” information between electronic devices
- Ex.) TV remote to a TV
- infrared light does not ionize atoms
89
define visible light
- represents the colors visible to the human eye
- visible light does not ionize atoms
- White light consists of all of the colors of the visible spectrum together
- The color black represents absorption of all of the color wavelengths
90
define ultraviolet
- causes darkening of the skin
- Ultraviolet light can be harmful
- causes skin cancer (by the activation of melanocytes)
- does not ionize the atoms
91
define x-rays
- used in medical imaging
- used in radiation therapy
- can ionize atoms
92
define gamma rays
- used in medicine imaging
- used in radiation therapy
- can ionize atoms
93
how are alpha/ beta particles similar to x-rays and gamma rays?
- they have the energy to ionize matter.
94
define particulate radiation
- physical particles originating from radioactive atoms with the ability to ionize matter
- alpha particles
- beta particles
95
define radioactivity
- process by which an atom with excess energy in its nucleus emits particles and energy to regain stability
96
define radioactive
- Elements that are composed of atoms with unstable nuclei
97
define radioactive decay
- process of a radioactive element giving off excess energy and particles to regain stability
98
define half-life
- the rate at which a radioactive substance decays
- length of time it takes for half the remaining atoms in a quantity of a particular radioactive element to decay
- used to measure radioactivity
99
true or false: alpha particles do not travel far
- true
- they're relatively large, so they cannot penetrate most objects
- attract electrons due to their positive net charge
100
define beta particles
- electron that is emitted from an unstable nucleus
- does not originate in an electron shell
- lighter and smaller
- can penetrate light materials
- have a much larger range and may ionize many atoms along their path
- may have a positive or negative charge
101
what's a positron?
- a positively charged beta particle
102
5. A diagnostic x-ray photon has a frequency of 2.42 × 10^19 Hz. What is its wavelength?
a. 12.4 × 10^−11 m
b. 12.4 × 10^27 m
c. 1.24 × 10^−11 m
d. 1.24 × 10^27 m
- c. 1.24 × 10^−11 m
103
6. A photon has a wavelength of 3 × 10−12 m. What is its frequency?
a. 3 × 10^−4 Hz
b. 3 × 10^20 Hz
c. 1 × 10^−4 Hz
d. 1 × 10^20 Hz
- d. 1 × 10^20 Hz
104
7. Which of the following do not originate from an unstable nucleus?
a. Alpha particles
b. Beta particles
c. X-rays
d. Gamma rays
c. X-rays
105
8. How much activity will remain in a dose of 20 mCI 99mTC after 24 hours? (The physical half-life of 99mTc is 6 hours.)
a. 5 mCi
b. 10 mCi
c. 0.05 mCi
d. 1.25 mCi
d. 1.25 mCi
106
9. The intensity of a source at 15 inches is 10 R. What will the intensity be at 45 inches?
a. 1.11 R
b. 0.74 R
c. 90 R
d. 304 R
a. 1.11 R
107
10. The intensity of a source is 25 R at 40 inches. What will the intensity be at 20 inches?
a. 6.25 R
b. 62.5 R
c. 100 R
d. 1000 R
c. 100 R
108
4. Which member of the electromagnetic spectrum has the longest wavelength?
a. Microwaves
b. Visible light
c. Radiowaves
d. X-rays
c. Radiowaves
109
3. Which of the following is not within the wavelength range of electromagnetic radiation?
a. 10^−24
b. 10^−12
c. 10^7
d. 10^−16
a. 10^−24
110
2. Which of the following members of the electromagnetic spectrum has the ability to ionize matter?
a. Radiowaves
b. X-rays
c. Microwaves
d. Ultraviolet light
b. X-rays
111
1. As the frequency of electromagnetic radiation decreases, wavelength will:
a. increase.
b. decrease.
c. remain the same.
d. frequency and wavelength are unrelated.
a. increase.
112
define protective housing
- provides solid, and stable mechanical support
- serves as an electrical insulator
- has a thermal cushion
- contains an oil bath
- absorbs most of the photons traveling in directions other than toward the patient
- reduces leakage radiation
113
what is the housing of the x-ray tube lines up with?
- housing is lined up with lead
114
what are the two notes of caution of the housing?
- caution of touching the tube (or housing) when it is on because of the heat
- high voltage cables should not be used as handles
115
what's the purpose of an x-ray tube?
- is an electronic vacuum tube that encloses the Anode, cathode, and an induction motor
- all enclosed in a glass/metal envelope
116
define Anode
- the positive side of the x-ray tube
- provides target for electron interaction to produce x-rays
- electrical and thermal conductor
- dissipate heat
117
define cathode
- the negative portion of the x-ray tube
118
what does the cathode consist of?
- the filaments and focusing cup
119
What's the main purpose of the enclosure
- to maintain a vacuum with the tube
- prohibit air electrons from entering the tube
120
what is the glass envelope made of?
- borosilicate glass
- pyrex
121
what's the purpose of the metal envelope?
- a constant electric potential between the electron Stream from the cathode and the enclosure
122
define target window
- desired exit point of the x-rays
123
what are the 2 types of Anode?
- stationary anode
- rotating Anode
124
define stationary anode
- the target does not move
- can be used in dental
- can be used for very small dosage techniques
- limited usage
125
what's a disadvantage of a stationary anode?
- the electrons would only hit one spot of the Anode
- the heat would built up rapidly, and damage the Anode/tube
- limits the exposure /usage
126
define rotating anode
- rotating disc made up of molybdeum coated with tungsten
- electrons hit multiple surfaces of the target, not just one spot
- rotated using an induction motor
- to spread the tremendous heat produced during x-ray production over a larger surface area
127
why is molybdenum so important?
- has a low thermal activity
- minimizes heat damage
- light but strong = easier to rotate
128
why is tungsten so important?
- very high melting point
- has a high atomic number
129
What are the major parts of the induction motor
- stator
- rotor
- bearings
130
define stator
- made up of electromagnets
- outside the tube enclosure
- stationary
- surrounds the rotor
- induces the turning of the rotor
131
define rotor
- within the enclosure
- continuously turn as the induced magnetic fields try to orient with the ever-changing external fields
- tube shaft attached directly to the Anode disk
- turns from the stator
132
define bearings
- in between the rotor
- low friction spheres
- allow free rotation of the rotor
133
define line-focus principle
- relationship between actual focal spot on the Anode and effective focal spot that extends from the Anode
134
what does the line-focus principle affect?
- heat capacity
- spatial resolution
- beam coverage
135
define actual focal spot
- area of the Anode where electrons turns into x-rays
- where all the heat is created
- a large focal spot is preferred
- the larger the size, the more the heat can spread out
- the side of the filaments determines the size of the focal spot
136
define effective focal spot
- the x-ray beam projected to the patient
- directly affects the creation of penumbra (shadows) and spatial resolution
- small effective spot is preferred
137
what is the range of target angles?
- 7-18 degrees
- 6-20 degrees
138
how does a small effective focal spot impact penumbra and spatial resolution?
- decrease penumbra
- increase spatial resolution
- indirect relationship
139
how does a large effective focal spot impact penumbra and spatial resolution?
- increase penumbra
- decrease spatial resolution
- indirect relationship
140
what is the goal of the line-focus principle?
- a large actual focal spot
- a small effective focal spot
- 10-20mm actual focal spot
- 1-2mm effective focal spot
141
what happens to heat capacity if there is a large actual focal spot?
- increase of heat capacity
- direct relationship
142
what happens to heat capacity if there is a small actual focal spot?
- decrease of heat capacity
- direct relationship
143
what are the characteristics of a small anode angle (6 degrees)?
- narrow effective focal spot
- well-aligned beam
- high spatial resolution
- reduces the size of the focal spot
- more heat
- less beam coverage (field size)
- small actual focal spot
- smaller exposure factors (mAs, kVp)
- used for extremities, dental, and mammography
144
what are the characteristics of a large Anode angle (20 degrees)?
- large actual focal spot
- larger exposure factors (mAs, kVp)
- larger effective focal spot
- lower spatial resolution
- larger beam coverage (field size)
- use din abdomen, pelvis, thoracic/lumbar spine
145
define Anode heel effect
- decreased x-ray beam intensity on an Anode side of the beam
146
define anode angle
- increases the area of the focal spot
- between 6-20 degrees
- increases the Anode to absorb heat
- helps decrease focal spot size
- increases spatial resolution
147
define cathode
- negative end of the tube
- provides the source of electrons needed to create the x-rays
- made up of filaments and a focusing cup
148
define thermionic emission
- boiling off of electrons
149
define focusing cup
- receives a strong negative from the secondary circuit that forces the electrons together into a cloud as they are boiled off of the filament
- made up of nickel
- surrounds each filament
- faces the Anode target
150
what's a pro about the Anode heel effect?
- places the least dense portion of the patient under the Anode side of the beam
151
what does an angled Anode cause?
- causes a variation of the beams intensity across the x-ray field
- the Anode (-) side is less intense (less photons)
- the Cathode (+) side is more intense (more photons)
152
why is the intensity of the Anode low compared to the cathode?
- some photons are created deep in the Anode
- photons get absorbed in the Anode heel, creating less intensity
153
What's the relationship between the anode angle and the Anode heel effect
- indirect relationship
- decreasing the Anode angle = increases anode heel effect = decreases beam intensity
- increasing the Anode angle = decreases the heel effect = increases beam intensity
154
what's the relationship between the SID and the Anode heel effect?
- indirect relationship
- decreasing SID = increases the Anode heel effect
- increasing SID = decreased Anode heel effect
- with less distance, you get more exposure of both anode and cathode
155
what's the relationship between the field size and the Anode heel effect?
- direct relationship
- increasing field size = increases Anode heel effect
- decreasing field size = decreases Anode heel effect
- when increasing, you gain more exposure on the Anode side
156
define space charge
- cloud of electrons
157
what are the 3 things needed to produce x-rays?
1. a large potential difference to give kinetic energy to the filament electrons (provided by the kVp setting)
2. a vehicle on which kinetic energy can ride (a quantity of electrons provided by mAs)
3. a place for interaction (the target of the anode
158
why do electrons get attracted to the Anode?
- get attracted from the huge potential difference
159
what are other factors of damaging the x-ray tube?
- very high exposure factors
- very long exposures
- overload of the filaments
- thermal characteristics
160
what are the three processes of heat transfer?
1. conduction of heat by heat-tolerant materials
2. radiation of heat energy from the anode to the oil bath
3. convection of heat into the room by the cooling fans
161
how much of energy is converted into photons (x-rays)? how much is converted into heat?
- 1% photons
- 99% heat
162
define HUs
- measure of the amount of heat stored in a particular device
163
what is the formula for HUs?
- kVp x mAs x s x c
- s is exposure time in seconds
- c is correction factor depending on the type of generator
164
what are the different types of correction factors?
- Single-phase = 1.0
- Three-phase, 6-pulse = 1.35
- Three-phase, 12-pulse = 1.41
- High-frequency = 1.45
165
what are some ways to extend tube life?
- the x-ray tube should be warmed before normal operation
- do not prep the rotor excessively
- do not routinely use extremes of exposure factors
166
4. A technique of 80 kV, 400 mA, 0.8 seconds is to be used on a 3-phase, 12-pulse machine. How many heat units are produced with a single exposure?
a. 25,600
b. 34,560
c. 36,096
d. 38,100
c. 36,096
167
5. The intensity of the x-ray beam is less:
a. in the center of the beam.
b. at the collimator.
c. on the cathode side.
d. on the anode side.
d. on the anode side.
168
6. Causes of tube failure are most often related to which of the following?
a. electrical characteristics
b. mechanical characteristics
c. physical characteristics
d. thermal characteristics
d. thermal characteristics
169
7. What metal is added to the filament to increase thermionic emission and extend tube life?
a. thorium
b. copper
c. rhenium
d. Tungsten
a. thorium
170
8. A small anode target angle:
a. results in an increase in anode heel effect.
b. results in a decrease in anode heel effect.
c. results in an equalization of anode heel effect.
d. does not influence anode heel effect.
a. results in an increase in anode heel effect.
171
9. A dual focus tube refers to a tube with:
a. two focal tracks.
b. two filaments.
c. two focusing cups.
d. two targets.
b. two filaments.
172
10. The purpose of the line focus principle is to create which of the following?
a. small actual and effective focal spot size
b. large actual and effective focal spot size
c. small actual and large effective focal spot size
d. large actual and small effective focal spot size
d. large actual and small effective focal spot size
173
11. A technique of 50 kV, 100 mA, 0.1 seconds is to be used on a 3-phase, 6-pulse machine. How many heat units are produced with a single exposure?
a. 500
b. 675
c. 705
d. 820
b. 675
174
1. Which of the following reduces leakage radiation to required standards?
a. x-ray tube
b. collimator
c. added filtration
d. protective housing
d. protective housing
175
2. Which component of the x-ray tube is responsible for concentrating the electron cloud?
a. anode
b. filament
c. focusing cup
d. focal track
c. focusing cup
176
3. The x-ray tube is a part of the:
a. x-ray circuit primary.
b. x-ray circuit secondary.
c. filament circuit.
d. breaker circuit.
b. x-ray circuit secondary.
177
Which of the following electromagnetic radiations have the lowest energy level?
- X-rays
- Radio waves
- Microwaves
- Visible light
- Radio waves
178
Which of the following helps to keep the x-ray tube cool on the inside of the protective housing?
- Target window
- Cooling fans and an oil bath
- Oil bath
- Cooling fans
Oil bath
179
The component of the nucleus that has a positive charge and mass is the
- neutron.
- none of these.
- electron
- proton
proton
180
The negative end of the x-ray tube is the
- target.
- envelope.
- anode.
- cathode.
- cathode.
181
X-rays are produced
- using fast-moving atoms.
- using fast-moving electrons.
- using fast-moving metals.
- from unstable atoms.
- using fast-moving electrons.
182
In terms of the x-ray tube, envelope is another name for the
- glass enclosure.
- anode
- cathode.
- induction motor.
- glass enclosure.
183
The three fundamental particles of the atom are the
- electron, nucleus, and proton.
- neutron, electron, and proton.
- nucleus, proton, and neutron.
- element, nucleus, and electron.
- neutron, electron, and proton.
184
The earliest atomic theory based on an arrangement similar to the solar system is attributed to
- Thomson.
- Bohr.
- Rutherford.
- Dalton.
- Bohr.
185
Which of the following is not part of the electromagnetic spectrum?
- Gamma rays
- Visible light
- Sound
- Microwaves
- Sound
186
The area of the envelope where x-rays should exit the tube is the
- x-ray gate.
- target door.
- x-ray trap.
- target window.
- target window.
187
The positive end of the x-ray tube is the
- envelope.
- filament.
- cathode.
- anode.
- anode.
188
The process of removing an electron from an atom is
- atomization.
- ionization.
- none of these.
- annihilation.
- ionization.
189
The two types of anode designs are stationary and
- traveling.
- all of these.
- rotating.
- dynamic.
- rotating.
190
Choose from the names of the parts below that are parts of the Magnetic Induction Motor for the X-Ray Tube.
[Select All That Apply]
- Bearings
- Filament
- Cathode
- Rotor
- Anode Target
- Focusing Cup
- Stator
- Bearings
- Rotor
- Stator
191
The atomic nucleus contains
- all of these.
- protons and neutrons.
- electrons and neutrons.
- protons and electrons.
- protons and neutrons.
192
As the wave’s frequency increases, the wavelength
- decreases.
- it depends on the type of electromagnetic radiation.
- increases.
- stays the same.
- decreases.
193
Frequency is typically measured in
- feet.
- hertz.
- meters.
- centimeters.
- hertz.
194
Tungsten is used to coat the anode disc because it
- has a low atomic number.
- has a high atomic number.
- has a low melting point.
- does not conduct heat well.
- has a high atomic number.
195
where does the negative energy come from in the filament?
- when voltage (kVp) is applied
- gives the filament a very strong negative charge
196
how do you de-energize an electron?
- the negatively charged electrons are attracted to the Anode
- because they are moving at a rapid pace, they crash into the Anode, stopping immediately
- when the crash happens, x-rays are created and heat is released
197
what was the first x-ray tube?
- the crookes tube
198
define the crookes tube
- simple tube with two electrodes at the opposite ends
- when kVp was delivered, the electrons would flow in a straight line
199
who invented the coolidge tube?
- Edward Coolidge
200
when was the coolidge tube invented?
- 1913
201
what are the parts of the x-ray tube?
- cathode
- anode
- window
- glass envelope
- filament
- focusing Cup
- anode stem
- anode disk
- housing (lead)
- induction motor
- stator
- rotor
- bearings
- anode Target
202
What are 3 steps in thermionic emission?
1. Heat up the Cathode
2. excessive production of electrons will create a space charge
3. the cloud of negative electrons will be attracted to the Anode
203
define sine waves
- a wave that goes up and down at a constant rate
204
what are parts of a sine wave?
- crest
- trough
- wavelength
- amplitude
- frequency
205
true or false: never get an x-ray lower than 70
- true
206
are both fans and oil bath inside the x-ray tube?
- no
- the fan sits outside of the tube
- the oil bath is inside of the tube
207
true or false: x-ray photons will react with matter (anode) to create a secondary photon
- true
208
define occupational exposure
- dosage of radiation a worker gains
- happens with Coherent and Compton
209
define primary beam
- 1st photons that were created
210
define incident photon
- the moment the photon hits the matter (patient)
- goes through the body
211
define attenuation
- photons that travel through the tissue
- loses energy, not as strong as the primary photon
212
define remnant
- the photon that leaves the patient
- leaves a black dot on the IR
213
how does fog occur?
- with interactions of matter
- with scatter x-ray interaction
214
define heterogenous or polyenergetic
- several/ multiple energies
- are the same
215
in a graph what 2 x-ray interactions will always be presentment?
- bremsstrahlung and characteristic
216
what 2 components (variables) are in the graph?
- kVp and mAs
217
What happens when there is an increase in quality?
- the image is clearer
- more details
218
define grid
- several black horizontal lines
- is radiopaque and radioluscent
219
define radiopaque
- radiation doesn't go through easily
- several thin layers of lead
- radiation has to go in between the lead
220
define radioluscent
- radiation can pass through
221
why does fog occur?
- the grid cannot stop scatter x-ray interaction
- scatter goes in between the grid (hits the radioluscent portion), resulting in fog
222
define fission
- splitting
223
define diverge
- separate/ move away from
- every photon that is produced, creates a diverging pattern
224
what happens when there is an increase in magnification?
- image distortion
225
what causes image distortion?
- movement, size, etc.
226
what happens when there is a high kVp?
- the higher the number, the higher the intensity
- this creates a higher penetration
227
define target interactions
- inside the tube
228
what are the 2 types of target interactions?
- bremsstrahlung
- characteristic
229
define matter interactions
- outside of the tube
- when photons interact with matter
- occur to the patient
230
what are 3 types of matter interactions
- compton
- coherent
- photoelectric
231
how much energy does bremsstrahlung carry?
- 90%
232
define bremsstrahlung
- redirecting an electron
- makes up most of the beam
- also known as breaking radiation
- no ionization
- because the inside of the atom is positive, an electron gets attracted to it
- due to the positive net charge, the electron changes its direction, completely ending up in a different pathway
- with that harsh turn (or change of direction), a photon is created
- primary beam
233
how much energy does characteristic carry?
- 10%
234
define characteristic
- lower energy
- loses energy
- never above 70 kVp
- ionization occurs (in the inner shell)
- energy is split
- an electron crashes into an electron in the inner shell (both going opposite directions)
- as it crashes, it creates a photon
- a cascade reaction occurs
235
define cascade reaction
- the remaining electrons will flow inward into the inner shell, closing the missing gap
- after, they'll go and search for another electron
236
what is the tingsten energy?
69
237
how much energy does Compton carry?
- 90%
238
What 2 interactions causes fog?
- Compton and coherent
239
define compton
- also known as Compton scatter
- primary source of occupational exposure
- occurs in the outer shell
- a primary photon is shot out
- photon hits an electron from the outer shell, creating a secondary photon
- secondary photon is weaker than the 1st
- causes ionization
- energy is split
- half of the energy knocks out the electron
- other half of the energy is the production of the secondary photon
- photon could potentially bounce back
- no cascade reaction
240
how much energy does photoelectric carry?.
- 10%
241
define photoelectric
- absorbed by matter
- also known as P.E
- ionization occurs (in the inner shell)
- where the primary photon crashes into an electron from the inner shell
- takes out way more energy to knock out an inner shell
- the secondary photon is VERY weak
- because of its weak strength, the secondary photon stays inside the patient's body
- P.E contributes to dose of radiation
- cascade reaction occurs
242
define coherent
- also known as classical scatter
- same energy in = same energy out
- no ionization
- occupational exposure
- the primary photon hits an electron from the outer shell
- the photon is too weak to knock it out
- the electron gains the energy of the primary photon
- because it's overstimulated with energy, it shakes, and releases that extra energy
- that energy released becomes the secondary photon
- no ionization
243
Which of the following interactions do not cause ionization?
- bremsstrahlung and coherent
244
which of the following interactions result in cascade reaction?
- characteristic
- photoelectric
245
which of the following interactions result in relatively higher energy photons?
- bremsstrahlung
- Compton
246
which of the following interactions is considered to be a source of occupational exposure?
- compton
- coherent
