Study Guide Flashcards
What happens to the energy spectrum when the kVp is decreased?
The amplitude and maximum voltage decrease
Area on the anode that DIRECTS the electrons to the focal spot during x-ray production
The focusing Cup
The x-ray intensity is less at the anode side of the x-ray beam than the cathode side of the x-ray beam. This is called
The heal effect
The low voltage on the x-ray tube
Creates the electrons
The following are component of the high voltage generator
Filament transform
High voltage transform
Voltage rectifier
The primary purpose of voltage rectification is
prevent electrons from striking the cathode
In an x-ray tube the electrons travel from
Cathode to Anode
Most x-rays produced in the target are
Bremsstrahlung
The probability of bremsstrahlung production is proportional to
to the Z square of the target materials
How will the x-ray energy spectrum change with an increase in mAs
Only the amplitude of the spectrum will increase
When filtration is added to an x-ray beam the average energy spectrum
shifts right and decreases amplitude
What is the first thing to happen in the production of characteristic x-rays
The orbital electron is ejected
Changing which of the following has the least effect on the average energy of the x-ray spectrum
mAs
The following is true of a modern x-ray tube
The anode is cooled by water and oil
it must have a vacuum
electrons are created by thermionic emission
Bremsstrahlung x-rays are created when
The incident electron loses energy
The x-ray tube mAs is a measure of the
charge produced
For a given energy beam, the penetration _______ with ______ atomic number
Increases, lower
Which of the following increases the quality of an x-ray beam
Increase filtration
Increasing filtration to an x-ray beam will decrease the
quantity of x-rays in the beam
Exposure is a measure of the
quantity of the beam
The intensity of the x-ray beam is directly proportional to the square of the
Potential, kVp
The intensity of the x-ray beam is inversely proportional to the square of the
Distance, d
The following affects x-ray quantity
Filtration
Beam Current
mAs
Increasing the energy of electromagnetic radiation is associated with
Increasing frequency
The double slit experiment is an example of how sub atomic particles
behave as a wave
The intensity of electrons created by photoelectric production can be increased by
Increasing frequency
When sub atomic particles are directed at a small single slit, the resulting distribution is
a single bunch pattern
The following will increase the number of photons in the x-ray spectrum
Increasing the atomic number, Z
Increasing the mAs
Increasing the kVp
Decreasing the filtration
The efficiency of the x-ray production increases with
Increasing kVp
When filtration is added to an x-ray beam the energy spectrum
Shifts right and decreases amplitude
Increasing filtration to an x-ray beam will decrease the
Quantity of x-rays in the beam
Which of the following will always increase the quality of an x-ray beam
Increases the kVp increase the filtration mAs has no effect
What type of interaction produces a photon of equal energy to the initial photon
Coherent
Which type of photon interaction requires a photon of at least 1.02 MeV
Pair Production
Which type of radiation interaction is predominant at diagnostic radiographic energies
Photoelectric
Which type of photon interaction is not inversely proportional to the photon energy
Pair Production
What interaction does not result in complete absorption of the photon
Compton
With which type of electrons does the photoelectric interaction usually occur
Inner shell electrons
Which of the following is a possible product after photoelectron
Characteristic x-ray and auger electron
The characteristic x-ray position will change location on the horizontal axis of the energy spectrum with a change in
Target material
Properties of photons
frequency, wavelength, velocity, amplitude
A reduction of radiation intensity due to scatter and absorption
attenuation
The energy of a photon is directly proportional
to its frequency
What is the source of radiation in an x-ray tube
the focal spot
Heel affect is caused by
the angle of the anode
The smaller the angle the
the larger the heel effect
Kvp is proportional to
Intensity
In an x-ray tube, the projectile is the _________
Electron
All electrons have the same ______, therefore electron kinetic energy is raised by raising the ________
Mass, kvp
Electrons traveling from cathode to anode constitute the x-ray tube current and are sometimes called ______ ________
Projectile Electrons
The production of heat in the anode increases _______ with increasing x-ray tube current
Directly
Doubling the x-ray tube current _______ the heat produced
Doubles
Heat production increases _______ with increasing kvp, at least in the diagnostic range.
Directly
Regardless of what mA is selected, the efficiency of x-ray production remains ________
Constant
The efficiency of x-ray production increases with increasing ______
kvp
If the projectile electron interacts with an inner shell electron of the target atom rather than with an outer shell electron, ________ x-rays can be produced
Characteristic
The transition of an orbital electron from an outer shell to an inner shell accompanied by the emission ________
X-ray
Similar characteristic x-ray are produced when the target atom is ________ by the removal of electrons of shells other than the K shell
Ionized
The effective energy of characteristic x-ray ________ with increasing atomic number of the target element
Increases
Bremsstrahlung radiation =
Bending radiation
________ x-rays are produced when a projectile electron is slowed by the nuclear field of an target atom nucleus
Bremsstrahlung
A projectile electron that completely avoids the orbital electrons as it passes through a target atom may come sufficiently close to the nucleus of the atom to come under the under the influence of its ________ __________
Electric field
Bremsstrahlung x-rays can be considered radiation that results from the _________ of projectile electrons by the nucleus
Braking
A change in mA or mAs results in a proportional change in the ______ of the x-ray emission spectrum at all energies
Amplitude
When _____ is increased, the relative distribution of emitted x-ray energy shifts to the right to higher average x-ray energy. The maximum energy of x-ray emission always remains numerically equal to the ______
kvp (kvp)
The ______ _______ of the target affects both the number (quantity) and the effective energy (quality) of x-rays
atomic number
Increasing target ______ ________ enhances the efficiency of x-ray production and the energy of _______ & Bremsstrahlung x-rays
atomic number, Characteristic
______ and __________ are target elements used for mammography
Molybdenum (Z=42) Rhodium (Z=45)
