what mag modes are available? - Correct Answer if you have a 16" II, you can have 12,9,6, and 4.5 "
Compton effect - Correct Answer hits the outer electron, incomplete transfer of energy, electron
released and a low energy xray is deflected
photoelectric absorption - Correct Answer x-ray totally absorbed by inner shell electron, x-ray
overcomes binding energy and knock out the electron and an outer shell electron takes it place. When
the outer electron moves to its new place, a characteristic x-ray is formed
what is the product of photoelectric absorption? - Correct Answer electron flying , characteristic x-ray,
and positive ion
coherent scatter - Correct Answer aka Thompson scatter, Rayleigh scatter or classical scatter. x-ray is
absorbed by entire atom and is sent off in another direction with no energy loss
does coherent scatter result in patient dose? - Correct Answer No, this reaction only causes excitation
of the atoms shells, but there is not energy transfer nor does the x-ray lose energy ( isotropic)
what is the chance of coherent scatter occurring? - Correct Answer 5%
attenuation - Correct Answer the drop of intensity of the beam due to absorption and scatter
photoelectric interaction is dependent on - Correct Answer Z^ 3 and 1/E^3
as photon energy increases there is more - Correct Answer penetration and a decrease in tissue
interactions
Compton is dependent on - Correct Answer energy level ( the higher it is, the greater probability of
occurrence), electrons/ gram
,attenuation equation - Correct Answer I= Io e^ (-ux)
initial energy x e^( attenuation factor x tissue thickness)= resulting energy
initial energy- resulting energy= absorbed energy
u ( tissue attenuation coeffient) is dependent on - Correct Answer keV and material
what is the source of free electrons? - Correct Answer cathode
what is the cathode made of? - Correct Answer 98% tungsten, 1-2% thorium
in what direction are electrons accelerated? - Correct Answer cathode to anode
how do we focus electron? - Correct Answer we use a focusing cup made of nickel that has a greater
negative charge. This negative charge repels and squishes the electrons that are made from thermionic
emission
how does deceleration occur in electrons? - Correct Answer the closer to the nucleus the electron is,
the more attraction there is and as a result it slows down faster. More energy is transferred to the xray
and it has a higher energy as well. If the electron is far, it wont slow down as much, it will lose less
energy and will result in a low energy electron.
what is the cathode filament made of? - Correct Answer Tungsten
bremsstrahlung interaction - Correct Answer 99% heat, 1% x-ray
aka braking radiation, cathode electrons hit anode electrons. Electron that are closer to the nucleus slow
down more and lose more energy but create higher energy electrons. Electrons that are farther away
slow down less, lose less energy and create low energy x-rays. They retain enough energy to keep having
more interactions
(electrons are more likely to hit the outer rim of the anode)
characteristic interactions - Correct Answer made 2 ways
,1)cathode electrons hit anode electrons
2) PE effect from x-ray to electron interactions
which interactions occur in the tube? - Correct Answer bremsstralung
what interactions occur in the body? - Correct Answer PE, Compton, Coherent scatter
what happens when we increase KeV? - Correct Answer the chance of Compton effect increases, and
the ratio between CS and PE also increases
equations for frequency and wavelength - Correct Answer c= speed of light= 3x10^8 m/s
Hertz= cycles/s
frequency = speed of light/ wavelength
v = c/ upside down Y
equation for energy - Correct Answer E= hv
h= 6.62 x 10^-34 Js = 4.15 x 10^-15 eVs
1 eV= 1.6 x 10^-19 Js
quality - Correct Answer overall energy of the beam
increase mAs= identical quantity
increase kVp= increase quality
increase filtration= increase quality
quantity - Correct Answer the amount of x-rays, this is directly proportional to mAs
primary radiation - Correct Answer x-ray beam after it leaves the x-ray tube and before it reaches the
object
, remnant radiation - Correct Answer radiation resulting after the x-ray beam exits the object
inverse square law - Correct Answer I1/I2 = D2^2/D1^2
fundamental properties of x-rays - Correct Answer 1) EMR travel in waves at the speed of light in a
certain direction in a straight light
2)can interact with matter
wave particle duality
tissue weighting factors - Correct Answer relative sensitivity , Wt
-can be used to convert partial radiation to whole body dose
radiosensitive factors - Correct Answer oxygenation of cell and cell cycle
Bergonie-Tribondeau law - Correct Answer cells that are rapidly dividing , undifferentiated and have a
long mitotic cycle are more sensitive to radiation
LET - Correct Answer linear energy transfer
alpha, protons = high LET
xrays and electrons= low LET
Wr - Correct Answer radiation weighting factor ; difference in biological damage from different types of
ionizing radiation
It is the same thing as RBE and Q
non-threshold - Correct Answer all dose levels are potentially harmful ( stochastic)
threshold - Correct Answer there is a radiation level when no effect can be observed
Compton effect - Correct Answer hits the outer electron, incomplete transfer of energy, electron
released and a low energy xray is deflected
photoelectric absorption - Correct Answer x-ray totally absorbed by inner shell electron, x-ray
overcomes binding energy and knock out the electron and an outer shell electron takes it place. When
the outer electron moves to its new place, a characteristic x-ray is formed
what is the product of photoelectric absorption? - Correct Answer electron flying , characteristic x-ray,
and positive ion
coherent scatter - Correct Answer aka Thompson scatter, Rayleigh scatter or classical scatter. x-ray is
absorbed by entire atom and is sent off in another direction with no energy loss
does coherent scatter result in patient dose? - Correct Answer No, this reaction only causes excitation
of the atoms shells, but there is not energy transfer nor does the x-ray lose energy ( isotropic)
what is the chance of coherent scatter occurring? - Correct Answer 5%
attenuation - Correct Answer the drop of intensity of the beam due to absorption and scatter
photoelectric interaction is dependent on - Correct Answer Z^ 3 and 1/E^3
as photon energy increases there is more - Correct Answer penetration and a decrease in tissue
interactions
Compton is dependent on - Correct Answer energy level ( the higher it is, the greater probability of
occurrence), electrons/ gram
,attenuation equation - Correct Answer I= Io e^ (-ux)
initial energy x e^( attenuation factor x tissue thickness)= resulting energy
initial energy- resulting energy= absorbed energy
u ( tissue attenuation coeffient) is dependent on - Correct Answer keV and material
what is the source of free electrons? - Correct Answer cathode
what is the cathode made of? - Correct Answer 98% tungsten, 1-2% thorium
in what direction are electrons accelerated? - Correct Answer cathode to anode
how do we focus electron? - Correct Answer we use a focusing cup made of nickel that has a greater
negative charge. This negative charge repels and squishes the electrons that are made from thermionic
emission
how does deceleration occur in electrons? - Correct Answer the closer to the nucleus the electron is,
the more attraction there is and as a result it slows down faster. More energy is transferred to the xray
and it has a higher energy as well. If the electron is far, it wont slow down as much, it will lose less
energy and will result in a low energy electron.
what is the cathode filament made of? - Correct Answer Tungsten
bremsstrahlung interaction - Correct Answer 99% heat, 1% x-ray
aka braking radiation, cathode electrons hit anode electrons. Electron that are closer to the nucleus slow
down more and lose more energy but create higher energy electrons. Electrons that are farther away
slow down less, lose less energy and create low energy x-rays. They retain enough energy to keep having
more interactions
(electrons are more likely to hit the outer rim of the anode)
characteristic interactions - Correct Answer made 2 ways
,1)cathode electrons hit anode electrons
2) PE effect from x-ray to electron interactions
which interactions occur in the tube? - Correct Answer bremsstralung
what interactions occur in the body? - Correct Answer PE, Compton, Coherent scatter
what happens when we increase KeV? - Correct Answer the chance of Compton effect increases, and
the ratio between CS and PE also increases
equations for frequency and wavelength - Correct Answer c= speed of light= 3x10^8 m/s
Hertz= cycles/s
frequency = speed of light/ wavelength
v = c/ upside down Y
equation for energy - Correct Answer E= hv
h= 6.62 x 10^-34 Js = 4.15 x 10^-15 eVs
1 eV= 1.6 x 10^-19 Js
quality - Correct Answer overall energy of the beam
increase mAs= identical quantity
increase kVp= increase quality
increase filtration= increase quality
quantity - Correct Answer the amount of x-rays, this is directly proportional to mAs
primary radiation - Correct Answer x-ray beam after it leaves the x-ray tube and before it reaches the
object
, remnant radiation - Correct Answer radiation resulting after the x-ray beam exits the object
inverse square law - Correct Answer I1/I2 = D2^2/D1^2
fundamental properties of x-rays - Correct Answer 1) EMR travel in waves at the speed of light in a
certain direction in a straight light
2)can interact with matter
wave particle duality
tissue weighting factors - Correct Answer relative sensitivity , Wt
-can be used to convert partial radiation to whole body dose
radiosensitive factors - Correct Answer oxygenation of cell and cell cycle
Bergonie-Tribondeau law - Correct Answer cells that are rapidly dividing , undifferentiated and have a
long mitotic cycle are more sensitive to radiation
LET - Correct Answer linear energy transfer
alpha, protons = high LET
xrays and electrons= low LET
Wr - Correct Answer radiation weighting factor ; difference in biological damage from different types of
ionizing radiation
It is the same thing as RBE and Q
non-threshold - Correct Answer all dose levels are potentially harmful ( stochastic)
threshold - Correct Answer there is a radiation level when no effect can be observed
