Brainscape's Knowledge GenomeTM

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


See full index

X-Ray Physics > Mid-Term > Flashcards

Mid-Term Flashcards

You may prefer our related Brainscape-certified flashcards:
Physics 101 flashcards AP® Physics flashcards
1
Q

What is an x-ray?

A

LIGHT; form of electromagnetic ionizing radiation; often called photons; has a wavelength much shorter than that of visible light; produced outside of the nucleus in the electron shells

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

What is another name for single x-ray in the beam?

A

photon

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

What determines the energy of the x-ray?

A

the amount of energy of each electron;

short wavelength= high frequency; long wavelength= low frequency

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

Do all of the x-rays in the beam have the same amount of energy?

A

no; different amounts of energy interacts with different matter

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

What is differential absorption?

A

difference between those x-rays that pass through tissue and those that don’t

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

What is radiographic density? How does a radiographically dense area appear on a radiograph?

A

mass per unit volume of black metallic silver; it’s a build up of blackness; it appears black metallic silver

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

How are radiographic density and anatomic density related?

A

inversely related

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

What is radiographic contrast?

A

degree of contrast between blacks and whites

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

How do we get contrast in an image? How does that happen?

A

differential absorption: differences in absorption that transmit the energy of the x-ray and absorption of the tissue

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

Is it really the x-ray that interacts with the film emulsion to produce the image?

A

No, it is the light from the rare earth screens

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

What would the film look like if all of the x-rays interacted with the emulsion and the film was then processed?

A

it will get black; when x-rays pass through the tissue, the energy will react with the film and produce blackness

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

What color of light do rare earth crystals typically emit?

A

green yellowish color

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

Define electromagnetic energy in terms of mass, charge, and velocity

A

no mass, no charge, travels at the speed of light

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

Define ionize

A

ability to totally remove an electron from it’s orbit around the nucleus

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

Which types of electromagnetic energies are able to ionize?

A

x-rays, gamma rays, some short UV rays

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

State the wave equation

A

velocity= frequency x wavelength

v) (f) (lambda

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

What is a gamma ray?

A

form of ionizing electromagnetic radiation; emitted from nucleus of a radioisotope and are usually associated with alpha or beta emission

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

What is the difference between x-rays and gamma rays?

A

origin; x-rays are located in the electron shells while gamma rays are from the nucleus

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

Why is a free electron a worry in human tissue?

A

Because they are highly reactive and believed to be involved in degenerative diseases and cancers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  1. List other types of electromagnetic energies in order of their energies relative to x-ray
A

Tv, radio, microwaves, infrared light, ultraviolet light, x-rays, gamma rays

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

range of x-rays in matter

A

1 – 100 meters in air

0-30 cm in soft tissue

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

What makes an x-ray photon higher energy than a microwave

A

the difference in wave frequency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
  1. HOW MUCH OF THE ELECTRIC AND KINETIC ENERGY OF THE PROJECTILE ELECTRONS IS CONVERTED TO HEAT? X-ray?
A

99%

<1%

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

Is heat production an excitation interaction or an ionization interaction?

A

excitation interaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What 2 methods are x-rays produced by?

A

characteristic and Bremsstrahlung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q
  1. WHICH OF THESE METHODS PRODUCES X-RAYS WHEN ELECTRONS SHIFT ENERGY LEVELS / SHELLS WITHIN THE ATOM?
A

characteristic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Tungsten is used as a target material. It has electron shells from “__” (near the nucleus) to “__” (outermost shell).

A

K”, “P”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which characteristic x-rays of tungsten are energetic enough to be useful?

A

K orbital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

AT LEAST ______ kVp IS REQUIRED TO PRODUCE USEFUL ENERGY K-CHARACTERISTIC X-RAYS OF TUNGSTEN.

A

69.53 kVp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

X-rays are converted from ___ energy to ___ energy.

A

kinetic, electromagnetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Does an alpha particle or x-ray cause a double strand break in DNA?

A

alpha particle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are the kVp values needed for each characteristic orbital?

A 
K=69.53
L=12.1
M=2.82
N=.6
O=.08
P=not bound
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

The vast majority of x-rays are produced by which production process?

A

Bremsstrahlung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q
  1. THE CHARACTERISTIC X-RAY WITH THE MOST KeV OF ENERGY OCCURS WITH THIS ELECTRON TRANSITION : _____TO _____.
A

P to K

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

In Bremsstrahlung production process, what is the range of energy?

A

0-125 kVp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the highest energy x-ray in a beam dependent on?

A

kVp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Describe the Bremsstrahlung x-ray production process.

A

main way xrays are produced. b/c nucleus is + and electron is -, the electron travels close to nucleus and gets drawn to it and deflected from its original direction. this deflection causes a loss of energy and that loss is formed into an xray photon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Describe the characteristic x-ray production process.

A

interaction of the projectile electron with the k-shell target electron. the electon is kicked out of its shell. an electron from an outer shell then fills in where the electron left. the energy level drops causing a photon to be emitted.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

WHAT IS THE AVERAGE ENERGY OF AN X-RAY BEAM PRODUCED AT 80 KVP?

A

1/3)*80 = 26.67 kVp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the purpose of the rectifier?

A

to let the electrical current flow in one direction, from cathode to anode, AC to DC, - to +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

whatt type of current is required to produce x-rays?

A

DC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What does the power company provide for us?

A

AC, alternative current

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What does kVp do inside the tube to produce x-rays?

A

it determines the quality of the x-ray beam

44
Q

Which type of rectification produces the highest contrast radiograph?

A

Full Wave Rectification

45
Q

Which type of rectification produces the highest energy x-rays, uses a 110 outlet, and reduces the patients exposure over 30%?

A

Hight Frequency rectification

46
Q

What is MAS?

A

of x-rays being produced

47
Q

What is kVp?

A

energy of x-rays

48
Q

What is isotropic emission?

A

360degrees divergence of light

49
Q

What is thermionic emission?

A

boiling off electrons

50
Q

What is a cathode?

A
  • negatively charged electrode
  • contains small and large filament
  • source of electrons for the production of x-rays
  • where electrons “boil” off
51
Q

What is a anode?

A
  • positively charged electrode
  • spinning disc
  • acts as a coolant by distributing heat
52
Q

What is the main function of the filter?

A

to reduce skin dose of radiation to the patient

53
Q

What is the x-ray tube made of?

A

blown glass or metal ceramic

54
Q

What is the advantage of the small filament?

A

produces a sharper image

55
Q

What is the advantage of the large filament?

A

shorter exposure time

56
Q

How is the filament/focal spot selected?

A

by selecting the mA

57
Q

What photographic property does mAs control?

A

density

58
Q

What electrical unit is set on the console to accelerate the electrons from cathode to anode?

A

kVp

59
Q

What photographic quality does the kVp control?

A

contrast

60
Q

What is contrast?

A

a photographic property that shows the degrees of difference between black, white and various shades of gray

61
Q

The anode spins at ___rpm.

A

3,600rpm

62
Q

How long should the anode spin after exposure is terminated to be sure there is no rotor bearing damage?

A

at least 90 seconds

63
Q

What type of motor spins the anode?

A

electrical induction

64
Q

What is the target area of the anode made of?

A

tungston

65
Q

The focusing cup has a strong _____ charge to keep the electrons focused into a small focal spot area on the target of the anode.

A

positive

66
Q

What is the tube housing lined with?

A

lead

67
Q

What is the tube housing filled with?

A

oil to dissipate heat

68
Q

What is the opening called that allows x-rays out of the housing tube?

A

port

69
Q

Define ALARA

A

As low as reasonably achievable

70
Q

Which rectification is most consistent with ALARA

A

Full Wave Rectification

71
Q

Which of these types of rectifiers will extend the tube life?

A

High Frequency Rectification

72
Q

Compare the cost of Full Wave Rectification to High Frequency Rectification.

A

HF is $3000 more

73
Q

How much of a change in mAs if underexposed?

A

increase 100%

74
Q

How much of a change in mAs if over exposed?

A

decrease 1/2

75
Q

increase in kVp would be an ___ of KE, to an ____ of x-ray energy (______wave length)

A

increase, increase, shorter

76
Q

the anode side of the tube can be located by:

A

negative label, positive label, listening for the spin, finding the wire for the AC current

77
Q

Which side of a radiograph will exhibit the least radiographic density?

A

The anode

78
Q

The high atomic # of the tungsten target absorbs low energy x-rays.

A

False

79
Q

Where should the anode side of the tube be placed when performing a lateral thoracic spine radiograph?

A

down

80
Q

Where should the anode side of the tube be placed when performing a lateral lumbar spine radiograph?

A

up

81
Q

Where should the anode side of the tube be placed when performing an AP thoracic spine radiograph?

A

up

82
Q

Where should the anode side of the tube be placed when performing a full spine radiograph on a 14 x 36” film?

A

up

83
Q

Where should the anode side of the tube be placed when performing a lateral cervical spine radiograph?

A

It doesn’t matter on a 10x12” film at 40”

84
Q

When the anode heel effect becomes important in terms of film size and source image distance (SID).

A

Large film sizes at short SID

85
Q

How does placing the anode / cathode side in the proper place affect the radiograph’s overall density.

A

It produces uniform in density

86
Q

Besides using the anode heel effect properly there are two other options that may help to produce a more uniform film density. They include:

A

Compensating Filters

Slow Speed where area is thin; faster speed where is thickest.

87
Q

How should you have your tube installed? (Which side up?)

A

anode

88
Q

Which side of the radiograph will be the sharpest?

A

anode

89
Q

The ____ side of the x-ray tube emits x-rays that are relatively perpendicular to the film.

A

anode

90
Q

State the unit that a physicist would use to describe ionizations in air in classical
nomenclature.

A

R

91
Q

State the unit that a physicist would use to describe ionizations in air in Systems
International nomenclature.

A

Coulombs/kg

92
Q

Coulombs/kg measure this type of radiation only:

A

X-ray and gamma

93
Q

State the unit for occupational exposure in classical nomenclature.

A

REM

94
Q

State the unit for occupational exposure in Systems International nomenclature.

A

Sievert

95
Q

___ mRem = 1 Rem

A

1,000

96
Q

State the formula for Rem. Rem = _____ x _____.

A

RAD x QF (quality factor)

97
Q

20 mRad of x-ray exposure = ____ mRem

A

20

98
Q

100 Rem = ______Sievert.

A

1

99
Q

State the unit of absorbed dose in classical nomenclature.

A

RAD

100
Q

State the unit of absorbed dose in Systems International nomenclature.

A

Gray

101
Q

100 Rad = _____Gray

A

1

102
Q

In x-ray: ____R = _____Rad = _____Rem

A

1,1,1

103
Q

Comparing annual radiation exposure to the population in the U.S., most exposure comes from this source:

A

background: cosmic, terrestrial

104
Q

List at least 3 consumer products that contribute to background exposure.

A

Tobacco, Television, Combustible Fuels

105
Q

State the annual whole body MPD for occupationally exposed persons in Rem.

A

5 REM

106
Q

State the average annual exposure that medical personnel receive.

A

< 100 mREM

X-Ray Physics (3 decks)

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