Particles associated with electromagnetic radiation that have no mass or electric charge are:
ions
negatrons
positrons
x-ray photons
x-ray photons
Coherent scattering is most likely to occur ____________, even though some of this unmodified scattering occurs throughout the diagnostic range and may result in small amounts of radiographic fog.
below 10 keV
between 30 keV and 60 keV
between 60 keV and 90 keV
above 100 keV
below 10 keV
Which of the following is not a type of interaction between x-radiation and biologic matter?
Compton scattering
Bremsstrahlung
Pair production
Photoelectric absorption
Bremsstrahlung
The symbol Z indicates the:
atomic number of an atom
atomic weight of an atom
fluorescent yield
number of vacancies in an atomic shell
atomic number of an atom
In photoelectric absorption to dislodge an inner-shell electron from its atomic orbit, the incoming x-ray photon must be able to transfer a quantity of energy:
less than the energy that binds the atom together
ten times as great as the energy that binds the atom together
as large as or larger than the amount of energy that binds the electron in its orbit
equal to or greater than 1.022 MeV, regardless of the energy that binds the electron in its orbit
as large as or larger than the amount of energy that binds the electron in its orbit
Which of the following interactions between photons and matter involves a matter-antimatter annihilation reaction?
Compton scattering
Coherent scattering
Pair production
Photoelectric absorption
Pair production
The probability of occurrence of photoelectric absorption _________ as the energy of the incident photon decreases and the atomic number of the irradiated atoms _________.
increases markedly, decreases
decreases markedly, increases
increases markedly, increases
stays the same, increases
increases markedly, increases
Which of the following terms refers to the radiation that occurs when an electron drops down from an outer orbit to fill a vacancy in an inner orbit of the parent atom?
Characteristic radiation
Bremsstrahlung
Photoelectric radiation
Primary radiation
Characteristic radiation
Fluorescent radiation is also known as:
characteristic radiation
coherent scattering
Compton scattering
unmodified scattering
characteristic radiation
What is the effective atomic number of compact bone?
5.9
7.4
7.6
13.8
13.8
Which of the following is not another term for coherent scattering?
Characteristic
Classical
Elastic
Unmodified
Characteristic
Which of the following are byproducts of photoelectric absorption?
Photoelectron and Compton scattered electron
Low-energy scattered x-ray photon and characteristic photon
Low-energy scattered x-ray photon and Compton scattered electron
Photoelectron and characteristic photon
Photoelectron and characteristic photon
Which two interactions between x-radiation and matter may result in the production of small-angle scatter?
Photoelectric absorption and Compton scattering
Coherent scattering and Compton scattering
Photoelectric absorption and pair production
Coherent scattering and pair production
Coherent scattering and Compton scattering
Which of the following particles is considered to be a form of antimatter?
Electron
Positron
X-ray photon
Scattered x-ray photon
Positron
Which of the following interactions results in the conversion of matter into energy?
Classical scattering
Photoelectric absorption
Modified scattering
Annihilation reaction
Annihilation reaction
Compton scattering is synonymous with:
coherent scattering
incoherent scattering
photoelectric absorption
photodisintegration
incoherent scattering
During the process of coherent scattering, the incident x-ray photon interacts with a(n):
single inner shell electron, ejecting it from its orbit
single outer shell electron, ejecting it from its orbit
atom transferring its energy by causing some or all of the electrons of the atom to vibrate momentarily and radiate energy in the form of electromagnetic waves
scattered photon of lesser energy, annihilating it
atom transferring its energy by causing some or all of the electrons of the atom to vibrate momentarily and radiate energy in the form of electromagnetic waves
What is the term for the number of x-rays emitted per inner-shell vacancy during the process of photoelectric absorption?
Characteristic absorption
Classical gain
Fluorescent yield
Modified pair production
Fluorescent yield
Which of the following results in all-directional scatter?
Classical interaction
Coherent interaction
Photoelectric interaction
Compton interaction
Compton interaction
Annihilation radiation is used in which of the following modalities?
Computed tomography (CT)
Digital mammography
Positron emission tomography (PET)
Computed radiography (CR)
Positron emission tomography (PET)
The x-ray photon energy required to initiate pair production is:
0.511 keV
1.022 keV
0.511 MeV
1.022 MeV
1.022 MeV
Differences in density level between radiographic images of adjacent structures as seen in a completed radiograph define:
image attenuation
radiographic contrast
radiographic density
photodisintegration
radiographic contrast
Radiographic density is:
caused by photodisintegration
defined as the degree of overall blackening on a completed radiograph
not affected by milliampere-seconds (mAs)
not relevant in the production of a diagnostic radiograph
defined as the degree of overall blackening on a completed radiograph
When a vacancy exists in an inner electron shell of an atom (as a result of photoelectric effect, Compton scattering, or bombardment by other electrons), the energy liberated when this vacancy is filled, instead of emerging from the atom as fluorescent radiation, can be transferred to another electron of the atom, thereby ejecting the electron. Such an emitted electron is called a(n) _____ electron.
Auger
Compton
Edison
Sievert
Auger
X-rays are carriers of:
disease
electrons
fluorescent properties that make them visible
manmade, electromagnetic energy
manmade, electromagnetic energy