Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Rad105 > Test 2 - Chpt 6 & 11 > Flashcards

Test 2 - Chpt 6 & 11 Flashcards

(81 cards)

Start Studying
1
Q

Two interactions that occur in the tungsten target

A

Characteristic
Bremsstrahlung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does heat production occur

A

When the electrons interact with the outer shell electrons of the tungsten target they cause excitation which causes excess energy to give off as infrared radiation (heat)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Characteristic Interactions

A

Filament electrons enters a target atom and strikes an orbital electron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How does characteristic interactions create photons?

A

If k shell electron is removed from orbit then an electron from the L shell drops to fill the vacancy. It does this by expending some of its PE which is given off as a photon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What shell is most likely to fill an inner shell

A

Adjacent shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

For characteristic photons, energy is dependent on the difference of what?

A

Of the binding energy between the shells involved

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Characteristic photon is named for the what?

A

For the shell being filled in each case
K characteristic = L electron filled a K vacancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How to find the energy of a characteristic photon

A

Binding energy of the farther shell is subtracted from that of the closer shell

(Inner shell - outer shell = photon energy)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What must happen for an orbital electron to be removed

A

Filament electron must have KE equal to or greater than the binding energy of the electron with which it interacts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

When the filament electron misses all of the orbital electrons and interacts with the nucleus of the atom

A

Bremsstrahlung interaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is a brems photon created?

A

When the filament electron slows down and changes direction because of the attraction to the nucleus it loses KE which is released as a photon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How to find the energy of a brems photon

A

By subtracting the energy that the filament leaves the atom from the energy it had when entering

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Why are most of the photons produced brems photons?

A
  • only k shells provide enough energy
  • orbital electrons are in constant motion so easy to miss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is added filtration placed?

A

Between the target window and the top of the collimator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Total number of x-ray photons in a beam

A

Beam quantity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is associated with beam quantity

A

Radiation dose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Intensity of a beam is inversely proportional to the square of the distance

A

Inverse square law

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What absorbs low energy photons that do not contribute to the image

A

Filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is beam quality?

A

The penetrating power of the x-ray beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What creates the dark shades of the image?

A

Photons that reach the image receptor 

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What creates the white or clear areas of the image?

A

Areas where no photons reach the image receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

The thickness of absorbing material necessary to reduce the energy of the beam to 1/2 its original intensity

A

Half value layer, HVL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the normal HVL of diagnostic beams

A

3-5 mm Al

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

The beam that exits the collimator and exposes the patient?

A

Primary beam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Beam that remains after interaction with the patient and is exiting the patient to expose the IR
Remnant beam
26
What is formed within the patient due to interactions with matter/tissue?
Secondary photons
27
For the emission spectrum graph what indicates a change in quantity
Y axis (number of x-rays)
28
For the emission spectrum graph what indicates a change in the quality
X axis (x-ray energy)
29
What five factors change the appearance of the x-ray emission spectrum
mA, kVp, tube filtration, generator type, and target material
30
If you decrease the quantity, what happens to the amplitude of the graph?
It decreases
31
If you increase mA what happens to the amplitude of both the continuous and discrete portions of the spectrum
Increases amplitude
32
If you increase kVp, what happens to the amplitude of both continuous and discrete portions of the spectrum in what way does it shift?
Amplitude increases Shift, right
33
An increase in tube filtration causes what to happen to the quantity and quality
Decrease in quantity Increase in quality
34
What is directly proportional to radiation quantity reaching the patient and the amount of remnant radiation reaching the IR
mAs
35
What is inversely related to exposure time to maintain exposure to IR
mA
36
What is directly proportional to radiation quantity
Exposure time
37
What is directly related to IR exposure
exposure time
38
Image brightness is adjusted during what and for what?
computer processing low and high exposure errors
39
what can exposure errors result in?
increased quantum noise visible
40
(T/F) Computer processing can fix overexposed, but not underexposed
true
41
What affects the amount of radiation exposure to the IR?
kVp
42
Too little radiation reaching the IR increases?
noise
43
The advantage of using the 15% rule
Changes exposure without changing patient dose (pregnant women & pathology)
44
How to maintain exposure when adjusting the kVp by 15%?`
Change mAs by a factor of 2
45
what is affected when altering the X-ray beams' penetrating power (2)?
absorption and transmission
46
increasing kVp does what to contrast?
decreases it
47
Higher kVp reduces the total number of what and increases what?
interactions the X-rays transmitted
48
What does the level of radiographic contrast desired depend on? (3)
- type and comp. of tissue - visualized structures - doc's pref
49
Focal spot size affects what of the image?
sharpness (detail/resolution)
50
What affects the amount of radiation reaching the patient?
SID
51
What type of relationship does SID and radiation intensity have?
inverse relationship
52
What is the inverse square law in WORDS >:{
the intensity of the X-ray beam is inversely related to the square of the distance from the source
53
Changing SID requires a change in what to maintain exposure to the IR?
mAs
54
Intensity directly relates to the square of what?
the distance
55
Direct square law AKA
Exposure maintenance formula
56
An increase in SID affects what (decrease or increase) (2)?
- image distortion decreases - spatial resolution increases
57
If you can't decrease OID how can you make up for it?
By increasing SID
58
Limiting scatter improves what?
quality and contrast
59
Why does using a grid increase patient dose?
Need to increase mAs
60
A larger field size increases what and causes what?
increases the amount of tissue irradiated causes more scatter radiation
61
A larger field size does what to contrast? why?
Decreases contrast - the amount of radiation reaching the IR has increased
62
exposure techniques and the amount of radiation output depend on what?
the type of generator used
63
generators with more efficient output require what to produce an image?
lower exposure technique settings
64
x-ray tubes operated above 70 kVp are required to have a minimum of what?
2.5 mm of aluminum filtration
65
increasing tube filtration increases the percentage of what?
higher-penetrating X-rays to lower-penetrating X-rays
66
What is beam attenuation?
What is left after scatter and absorption
67
part thickness affects what?
beam attenuation
68
(T/F) increasing or decreasing part thickness requires a change in mAs to maintain exposure to the IR?
True
69
What establishes the environment for X-ray production?
The removal of the orbital electron
70
What produces characteristic X-rays once the environment is set?
the expending of energy during the cascade
71
Will there be K-shell interactions if a radiographer selects a kVp that's lower than 70?
No, for tungsten it must be equal to or greater than 69.5 keV
72
(T/F) Bremsstrahlung interactions come from the loss of KE from the filament electron
true
73
(T/F) The closer the filament electron gets to the nucleus the weaker the attraction
False -The attraction is stronger
74
(T/F) The more energy the filament electron gains the stronger the resultant brems photon
False -The more energy the electron loses
75
The average energy of a brems photon is what of the kVp selected at the control panel?
1/3
76
What is the primary contributor to inherent filtration, equating to about 0.5 mm Al Equivalent?
target window
77
K-characteristic photons' energy range
57-69 keV
78
What type of relationship do mAs have with the exposure reaching the IR?
Direct proportional
79
What type of relationship does mA and time to maintain exposure to the IR?
Inverse Proportional
80
Given the anatomic part is adequately penetrated, changing the kVp will affect what (2)?
Scattering and contrast
81
The amount of remnant radiation will decrease when you increase what?
tissue thickness

Rad105 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions