C1- Radiologic Physics Flashcards
(118 cards)
1
Q
It is a German word that means “slowed down radiation”
A
Bremsstrahlung
2
Q
What is the x-ray spectrum of Bremsstrahlung radiation?
A
Continuous
3
Q
Where does the Bremsstrahlung radiation interacts?
A
Nuclear Field
4
Q
All characteristics x-rays are useless except for what kind of x-ray?
A
K - x-ray because they have enough energy that is within the diagnostic range (20-150)
5
Q
Substance that comprises all physical objects
A
Matter
6
Q
Fundamental building blocks of matter
A
Atom
7
Q
What is the atomic mass unit of proton
A
1.673 x 10^-27
8
Q
What is the atomic mass unit of neutron
A
1.675 x 10^-27
9
Q
What are the 4 essence in Medieval atom theory?
A
Dry, Cold, Hot, Wet
10
Q
Who made the hook and eye theory?
A
John Dalton
11
Q
He made the chemical table of elements
A
Dmitri Mendeleev
12
Q
He made the plum pudding model
A
Joseph John Johnson
13
Q
He made the plum pudding model
A
Joseph John Johnson
14
Q
Who and when was the Rutherford Atom made?
A
Ernest Rutherford, 1911
15
Q
It is the ability to do work
A
Energy
16
Q
What is the unit for energy?
A
Joule
17
Q
What is the unit for energy?
A
Joules
18
Q
Explain Law of Conservation of Energy
A
It states that energy cannot be created nor destroyed but can be transferred from one form to another.
19
Q
Who made Theory of Relativity and what is it?
A
Albert Einstein
Matter can be converted to energy and energy to matter
20
Q
Who made Theory of Relativity and what is it?
A
Albert Einstein
Matter can be converted to energy and energy to matter
21
Q
The principal parts of atom
A
- Nucleus
- Orbital shells
22
Q
Atoms means
A
Indivisible
23
Q
The fundamental particles of atom
A
- Protons
- Neutrons
- Electrons
24
Q
The importance of Dalton Atom
A
- It presents that atoms are specific to each element
- Chemical bonding
25
Explain the difference between Bohr Atom and Rutherford atom
Rutherford Atom (1911)- Small dense positively charged center surrounded by a cloud of electrons
Bohr Atom (1913)- Electrons are in an orbit or it is a miniature solar system
26
Another term for outer shell
Valence Shell
27
Atomic mass unit is based on
1/12th of the Carbon Atom
28
What determines the atomic number of an element?
Protons
29
True or False:
# Protons = # Electrons
True
30
This contributes to the overall mass of the atom and involved in the strong nuclear force that holds the nucleus together
Mass and Force
31
This contributes to the atomic mass of an element
Neutrons
32
The first table of elements has how many elements
60 elements
33
Groups is based on the..
How many electrons are on the valence shell
34
The Period on the periodic table of elements are based on the..
How many shells are on the chemical
35
What is the formula for determining the number of electrons in the each shell
2n^2
36
It is the strength of attachment of an electron to the nucleus
Electron Binding Energy
37
What is Electron Binding Energy?
-It is the strength of attachment of an electron to the nucleus
-It is the energy required to ionize electron
38
True or False:
The greater the total number of electrons in an atom, the more tightly each is bound
True
39
The letter to signify atomic mass number?
A in the upper left of chemical symbol
40
The letter that signify the atomic number of an element
Z in the lower left corner of the chemical element
41
It is the ability to do work
Energy
42
Radiation is the energy…
emitted and transferred through space
43
This reduces the electrostatic repulsion between positively
charged protons.
Neutron
44
The by product of ionization
Ion pair
45
States that the sum of all matter and energy is constant
Law of Conservation of Energy
46
Theory of relativity formula
E=mc^2
47
Energy emitted and transferred through space (in a form of a wave)
Radiation
48
Any type of radiation capable of removing an orbital e- from the atom with which it interacts
Ionizing Radiation
49
Addition of energy to a system achieved by raising the energy of electrons with the use of x-rays
Excitation
50
By product of excitation
Heat or Light
51
Gamma rays and X-rays differ in
Origin
52
Particulate or Electromagnetic:
Has mass and charge
Particulate
53
Particulate or Electromagnetic:
Has no mass and no charge
Electromagnetic
54
the spontaneous emission of particles and energy in order to become stable.
Radioactivity
55
What is the rate of decay/disintegration of radioactive material
Radioactivity
56
Radioactivity is expressed in
Conventional unit:
SI unit:
Curie
Becquerel
57
The atoms involved and the only nuclei that undergo radioactive decay
Radionuclide
58
The process by which the nucleus spontaneously emits particles & energy & transforms itself into another atom to reach stability
Radioactive Decay/ Radioactive Disintegration
59
Alpha emission only occurs on ________
Heavy radioisotopes
60
Alpha emission is consists of ___ protons & ___ neutrons and results in ___ atomic mass number.
2, 2, 4
61
Alpha emission :
Energy:
4-7 MeV
62
It occurs in all radioisotopes
Beta emission
63
It occurs more frequently than alpha emission
Beta emission
64
Beta emission has ______ beta particle has a range of about _____ in soft tissue
2-MeV: 1 cm
65
Occurs in a neutron-rich (proton deficient) nuclei.
Beta minus decay
66
Occurs in a neutron-deficient (proton rich) nuclei.
Beta plus decay
67
Occurs in a neutron-deficient (proton rich) nuclei.
Beta plus decay
68
A decay involving emission of gamma radiation.
Isomeric Transition
69
It is an inverse photoelectric effect This happens when gamma radiation from the nucleus ejects an electron on its way out.
Internal Conversion
70
By product of Internal Conversion
Auger electron
71
The time required for a quantity of radioactivity to be reduced to one-half its original value
Radioactive Half-life
72
Amount of time half of radioactive compound is eliminated from body
Biologic Half-life
73
Amount of time half of radioactive compound is eliminated from body via radioactive decay and biological excretion
Effective Half-life
74
This is the smallest unit of electromagnetic energy
Photon
75
What are the properties of electromagnetic energy
Frequency, wavelength, velocity and amplitude
76
True or False:
Velocity is the same regardless of whether it is in a wave or particle form.
True
77
Speed of light
3x10^8 meters/second or 186,000 miles/second
78
The width/height of the waveform or this is one-half range from crest to valley
Amplitude
79
What is the relationship of amplitude yo frequency or wavelength?
Do not have effect
80
The rate of rise and fall
Frequency
81
SI unit of frequency
Hertz
82
1 Hertz is equal to
1 oscillation/second
83
The distance of one crest to another
Wavelength
84
The relationship of wavelength to frequency
Inversely proportional
85
Relationship of frequency to energy
Directly proportional
86
The period of a wave is the _________for one complete cycle.
time of the wave
87
Any type of radiation that causes excitation
Non-ionizing radiation
88
The by products of non-ionizing radiation are
Heat and light
89
The function of x-ray image system
Convert electrical energy to electromagnetic energy
90
What are the conditions needed for x-ray production?
• Large potential difference (kVp) •Quantity of electrons (mAs)
• A place of interaction (target)
• Source of electrons (filament)
91
What is projectile electron?
•Electrons travelling from cathode to anode
• It interacts with the orbital electrons or nuclear field of
target atoms
92
Answers the following
Anode Heat Production:
Where:
What:
How:
Where: Outer Shell
What: Excitation
How:
93
Answers the following
K characteristics:
Where:
What:
How:
Where: Inner shell
What: ionization
How: Projectile electron removes the electron in inner shell which made the outer shell electron fills in inner void
94
This increases directly with increasing x-ray tube current & kVp
Anode heat
95
Answers the following
Bremsstrahlung x-ray:
Where:
What:
How:
Where: Nuclear Field
What: slowing down of electrons
How: Projectile electron is slowed by the nuclear field of a target atom nucleus.
96
In K-Characteristics effective energy ↑ = Atomic Number of the element
↑ Atomic Number of the element
97
Low energy x-rays interacts with
Whole atom
98
Moderate energy x-rays interacts with
Electrons
99
High energy x-rays interacts with
Nucleas
100
Coherent Scattering is also known as
Classical scattering and Thompson Scattering
101
Coherent scattering happens when the x-ray has how much energy
Less than 10 kev
102
Coherent scattering happens when the x-ray has how much energy
Less than 10 kev
103
Answer the following:
Coherent Scattering
What:
Where:
How:
Results:
Where: Whole target atom
What: Excitation
How: Release of excess energy
Results: Scattered x-ray
104
True or False:
In a coherent scattering the energy of the incident x-ray is not equal to the energy of the scattered
False because the energy of the incident x-ray is equal to the energy of the scattered and the only difference is the change in direction
105
Answer the following:
Compton Effect
Energy:
Where:
What:
How:
Result/s?:
Compton Effect
Energy: within diagnostic range (30-150 kev)
Where: Outer Shell Electron
What: Ionization
How: The incident x-ray partially deposited energy to the electron which made it ionized
Result/s?: Compton Electron and Scattered x-ray
106
Increased angle of deflection = energy is transferred to the Compton electron
More energy
107
Relationship of x-ray energy to the chances having a Compton Interaction
Inversely Proportional
108
True or False:
Compton Scattering is independent to the atomic number
True
109
The effect of Compton Scattering are:
1. Occupational Dose
2. Reduces image contrast
3. Secondary radiation
4. Provides gray tones in the radiographic image
110
Answer the following:
Photoelectric Effect:
Energy:
Where:
What:
How:
Result/s?:
Answer the following:
Photoelectric Effect:
Energy: Diagnostic Range
Where: Inner Shell Electron
What: Ionization
How: Full deposition of energy = removal of electron
Result/s?:
1. Photoelectron
2. Secondary X-rays (Characteristic)
3. No scattered x-ray
4. Total x-ray absorption
111
What is the relationship of the x-ray energy to the probability of Photoelectric effect
Inversely proportional
112
The relationship between the atomic number and photoelectric interaction
Directly proportional
113
Effects of photoelectric interaction
1. Patient Dose
2. Produces a high contrast image
3. White shades in the radiographic image
114
Answer the following:
Pair Production:
Energy:
Where:
Result/s:
Pair Production:
Energy: >1.02 MeV
Where: Nuclear Field
Result/s: Pair = Electron and Positron
115
This is the process where the positron meets an electron and be converted into energy
Annihilation radiation
116
Answer the following:
Photodisintegration
Energy:
Where:
What:
Result/s:
Photodisintegration
Energy: >10 MeV
Where: Nucleus
What: Excitation
Result/s: Nuclear Fragment
117
What are the results of photodisintegration?
Results:
• Incident photon disappears
• Nuclear excitation
• Emission of nuclear particle
• Proton
• Neutron
• Alpha particle
118
Relationship between the kVp and differential absorption
Inversely proportional
