Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

physics > chapter 8 & 9 ( x ray production and emission ) > Flashcards

chapter 8 & 9 ( x ray production and emission ) Flashcards

1
Q

A change in_____
has no effect on the position of the discrete x-ray emission spectrum.

A

a.kVp
b.mAS
c.filtration
d.waveform

(All of the above)

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

A compensating filter is used with a body part of_____
thickness to create______
optical density in the image.

A

non-uniform, uniform

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

Added filtration results in_____

A

a.reduced X-ray quantity
b. an increase in the quality of the beam c.increased HvL
d. reduced patient dose

(All of the above)

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

A filtered diagnostic X-Ray beam at 80 kVp contains

A

mostly bremsstrahlung, with some characteristic X-Rays

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

A minimum HVL is required for diagnostic X-Ray beams because

A

a lower HVL would result in an increased absorbed dose to the patient with no improved image quality

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

An exposure taken at 100 kVp would have a maximum energy of
keV.

A

100

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

An exposure taken at 100 kVp would have an average energy of about
keV.

A

33

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

An exposure taken at 100 kVp would have an effective characteristic X-Ray energy of
keV.

A

70

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

An increase in kVp would_____
the______
of the emission spectrum

A

increase, amplitude and peak location (shift right)

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

Approximately_______
of the kinetic energy of the projectile electrons is converted to X-Rays at the target.

A

1%

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

An X-Ray beam can be made to have higher average energy if which of the following occurs?

A

Filtration is added

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

As filtration is_____
beam quality is_______
and quantity is______

A

increased, increased, decreased

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

As the number of pulses in the generator voltage waveform
the _______amplitude of the X-Ray spectrum________
and the peak shifts to the_____

A

increases, increases, right

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

Changes in______
result in directly proportional changes in only the amplitude of the emission spectrum

A

mAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Characteristic X-Rays_____

A

are electromagnetic radiation

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

Characteristic X-Rays are produced when

A

a vacancy in the electron orbit is filled

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

Characteristic x-rays energies are directly affected by:

A

Target material (Z)

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

Electron interactions at the inner shell of the target atoms produce______
radiation.

A

characteristic

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

Factors that can change the X-Ray spectrum are all of the following except

A

focal spot

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

How does an increase in filtration affect the emission spectrum?

A

reduced amplitude and a shift to the right

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

If filtration is removed from the X-Ray beam, then the HVL

A

decreases

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

If the distance from the source of X-Rays is increased by a factor of two, how is the X-Ray intensity at the image affected?

A

It is reduced by a factor of four

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

If the kVp is increased, then the HVL

A

increases

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

If the mAs is increased, then the HVL

A

stays the same

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

If the technique changed from 80 kVp to 65 kVp, you would expect the peak of the bremsstrahlung spectrum to

A

shift to the left and decrease in amplitude

25
Q

If the tube is brought closer to the patient and the technique is not changed, then the HVL

A

stays the same

26
Q

If X-Ray quantity is increased, what happens to the digital image?

A

It becomes better or clearer

27
Q

Increasing the_____
in digital imaging, ______
the image contrast

A

mAs, does not increase

28
Q

Inherent filtration______

A

slightly increases over the tube’s lifetime

29
Q

In order for a characteristic X-Ray to be produced, the energy must be______
the binding energy of the inner shell electron.

A

greater than

30
Q

lonization occurs due to

A

coulombic repulsion

31
Q

Penetrability of an X-Ray beam describes X-Ray

A

quality

32
Q

The 2nd HVL for a monoenergetic beam is______
the 1st HVL.

A

equal to

33
Q

The 2nd HVL for polyenergetic beam is______
the 1st HVL.

A

greater than

34
Q

The bremsstrahlung process produces X-Rays when

A

electrons are slowed in the anode

35
Q

The efficiency of X-Ray production slightly increases as_____
increases.

A

kVp

36
Q

The HVL is____

A

the thickness of a material to reduce the beam intensity to half the initial intensity

37
Q

The main purpose of added filtration is to reduce____

A

patient dose

38
Q

The number of useful X-Rays in the beam defines X-Ray

A

quantity

39
Q

The useful characteristic X-Rays in diagnostic radiology are from tungsten targets are_____
X-Rays.

A

K-shell

40
Q

The X-Ray emission______
is a plot of______

A

spectrum, number of X-Rays vs energy

41
Q

The X-Ray quality is____

A

not related to mAs

42
Q

The X-Ray quality______
when distance_____

A

does not change, is changed

43
Q

The X-Ray quality______
when kVp____

A

decreases,decreases

44
Q

The X-Ray quantity is___

A

directly related to mAs

45
Q

The X-Ray quantity is

A

directly related to kVp^2

46
Q

The X-Ray quantity is

A

inversely related to distance^2

47
Q

What happens to X-Ray penetrability as beam quantity increases?

A

Nothing, quantity is not effected by penetrability.

48
Q

When comparing the emission spectra of molybdenum with tungsten, both at 80 kVp and 20 mAs:

A

molybdenum characteristic X-Rays will have lower energies than tungsten

49
Q

Where are the lowest energy X-Rays that are produced most likely to be absorbed?

A

in the tube target

50
Q

Which clinical X-Ray exam is likely to have Characteristic X-Rays in the useful beam?

A

Chest x rays

51
Q

Which interaction involves production of Bremsstrahlung X-Rays?

A

Radiative

52
Q

Which interaction involves production of Characteristic X-Rays?

A

ionization

53
Q

Which interaction involves production of infrared photons?

A

Excitation

54
Q

Which of the following, if it is the only thing changed, will increase noise on the digital image?

A

a. Increased source to image distance
b. Reduction of kVp
c. I ncrease in filtration
2 d. Reduction of mAs

(e. All of the above)

55
Q

Which of the following is a compensating filter?

A

a. trough
b. wedge X
c.bow tie
d.boomerang

(e. All of the above)

56
Q

Which of the following transition results in the highest energy characteristic X-Ray?

A

O to K

57
Q

X-Ray intensity can be changed by changing

A

a.
distance X
F Flag question
b. filtration
C.
kVp
d. mAs

(e.
All of the above)

58
Q

X-Ray quality is measured in

A

half-value layers (HVL)

59
Q

X-Ray quantity is_____
filtration.

A

exponentially related to

60
Q

X-Ray quantity is measured in

A

Roentgens (R)

61
Q
A

physics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions