Which of the following is a correct description of the relationship between the wavelength and frequency of the x-ray photon?
Select one:
C. Frequency and wavelength are inversely related.
X-rays are invisible.
Select one:
True
False
True
X-rays cannot be focused with a lens.
Select one:
True
False
True
The first Nobel Prize for physics was received in 1901 by:
Select one:
a. Crookes.
b. Wilhelm Roentgen.
c. Marie Curie.
d. Einstein.
Wilhelm Roentgen.
The distance between two successive crests of a sine wave is known as:
Select one:
B. Wavelength
X-rays are able to interact with certain materials and produce light energy.
Select one:
True
False
True
When were x-rays discovered?
Select one:
B. November 8, 1895
Since Roentgen's discovery in the late nineteenth century, we have learned an enormous amount about the properties of x-rays.
Select one:
True
False
False
The frequency of a wave is the number of waves passing a given point per given unit of time. Frequency is measured in:
Select one:
D. Hertz
When first developed, the branch of medicine using x-rays was called:
Select one:
D. Roentgenology
The letter “x” in x-ray is the symbol for:
Select one:
A. the unknown.
An x-ray beam that has photons with many different energies is:
Select one:
D. Heterogeneous
Name the type of interaction shown here.
Select one:
C. Charictaristic
The _____ is the portion of the x-ray tube that contains the filament.
Select one:
B. Cathode
In diagnostic imaging, most x-ray photons are produced by ___________ interactions.
Select one:
C. Bremsstrahlung
With a standard x-ray tube, _____% of the x-ray beam produced with 90 kVp is the result of characteristic interactions.
Select one:
B. 15
The x-ray beam produced with 120 kVp will consist primarily of x-rays produced by bremsstrahlung interactions.
Select one:
True
False
True
Match the letter to the appropriate term to label the diagram of an x-ray tube.
F – Anode
D – Filament
B – Target
A – Stator
G – Cathode
C – Glass envelope
E – Rotor
The electrical energy applied to an x-ray tube will be transformed to:
Select one:
C. A and C
X-ray photon energy is measured in:
Select one:
B. keV
What are the 2 types of interactions that accelerated electrons have with the target to produce x-ray photons?
Select one or more:
a. Bremsstrahlung
b. Compton
c. Characteristic
d. Photoelectric
Bremsstrahlung, Characteristic
Calculate the mAs:
150 mA, 100 ms
15 mAs
Decreasing the exposure time results in:
Select one:
C. Fewer x-ray photons
True or False:
Space charge effect refers to the tendency of the space charge to not allow more electrons to be boiled off the filament.
Select one:
True
False
True
The focusing cup focuses:
Select one:
A. Stream of electrons
The focusing cup:
Select one:
A. Has a negative charge
Electrons can flow from cathode to anode or from anode to cathode during the x-ray exposure.
Select one:
True
False
False
How fast does the anode rotate?
Select one:
A. 3,000 to 10,000 RPM
mA has a __________ relationship with density.
Select one:
D. direct
Inside the x-ray tube envelope you will find:
Select one:
a. Oil
b. Air
c. A and B
d. None of the above
None of the above
Tungsten has a ________ atomic number and a _________ melting point.
Select one:
C. High, high
Kilovoltage controls the
Select one:
D. speed of the electrons
mA is a measure of _____ that flows from cathode to anode.
Select one:
B. Tube current
Select all the components of the cathode
Select one or more:
a. Focusing cup
b. Rotor
c. Filament
d. Stator
e. Target
Filament, Focusing cup
The speed of electrons controls the:
Select one:
A. quality of the x-rays
Define thermionic emission
Select one:
A. Boiling off of electrons from the filament
The positive side of the x-ray tube is the:
Select one:
B. Anode
Increasing the kVp will do which of the following?
Select one:
D. B and C
In order to produce x-rays, electrons must be:
Select one:
D. All the above
Define density
Select one:
D. The overall blackness produced on the image after processing.
Which component is the source of electrons?
Select one:
D. Filament
Exposure time has a __________ relationship with density.
Select one:
C. direct
As kVp increases, beam penetrability:
Select one:
A. increases
Define anode
Select one:
C. Positively charged electrode
Calculate the mAs: (units in mAs)
50 mA, 200 ms
10 mAs
Which element is used to make the filament?
Select one:
B. Tungsten
The highest energy x-ray photons produced with a 100 kVp exposure will be:
Select one:
B. 100 keV
Which has the GREATER radiographic density?
B
With a standard x-ray tube, ____% of the x-ray beam produced with 65 kVp is the result of bremsstrahlung interactions.
Select one:
C. 100
The device that nearly surrounds the filament is the:
Select one:
D. Focusing cup
With a standard x-ray tube, ____% of the x-ray beam produced with 65 kVp is the result of characteristic interactions.
Select one:
B. 0
Doubling the mAs has what affect on density?
Select one:
D. doubles
Select all the components of the anode
Select one or more:
a. Filament
b. Stator
c. Rotor
d. Target
e. Focusing cup
Stator, Rotor, Target
Name the type of interaction shown here.
Select one:
D. Bremsstrahlung
Bremsstrahlung is German for:
Select one:
A. "Breaking radiation"
mA and time control the ________ of the x-ray beam.
Select one:
quantity
quality
quantity
The part of the x-ray tube that is connected to the target and causes it to turn is the:
Select one:
C. Rotor
The quality of the x-ray beam indicates:
Select one:
B. The ability of the photons to penetrate
A dual-focus tube has two:
Select one:
A. Cathode filaments
What is the name of the exact area on the anode that is struck by the electron stream?
Select one:
C. Focal spot
When making an exposure, which of the following does not occur when just the rotor, or prep button, is activated?
Select one:
C. Voltage is applied across the tube.
Filament current is approximately:
Select one:
a. 0.5 to 2 milliamperes
b. 3 to 5 milliamperes
c. 0.5 to 2 amperes
d. 3 to 5 amperes
3 to 5 amperes
kVp controls the _________ of the x-ray beam.
Select one:
quality
quantity
quality
Calculate the mAs:
200 mA, 0.10 s
20 mAs
Bremsstrahlung interactions are associated with K-shell electrons being from its orbit.
Select one:
True
False
False
How much energy in an exposure is converted to x-ray photons?
Select one:
B. approx 1%
Doubling mA results in:
Select one:
D. All of the above
What is the name of the device in a rotating anode x-ray tube that turns the rotor?
Select one:
C. Stator
The speed the electrons inside the x-ray tube travel is:
Select one:
C. Approximately one half the speed of light
According to the line focus principle, as the target angle decreases, the _______.
Select one:
C. effective focal spot size decreases
To double the density of a 90 kVp exposure using only a change in kVp, what would the new kVp be? (Rounded to the nearest whole number, units in kVp)
104 kVp
Define contrast:
Select one:
A. photographic factor that effects the visibility of recorded detail
Effective focal spot size refers to focal spot size as measured directly under the anode target.
Select one:
True
False
True
The advantage to having a focal track is that:
Select one:
D. Higher exposure factors can be used.
As kVp increases, beam penetrability:
Select one:
A. increases
Low energy photons are desirable in the x-ray beam because they contribute to image quality.
Select one:
True
False
False
Actual focal spot size refers to the size of the area on the anode target that is exposed to electrons from the tube current
Select one:
True
False
True
If a person stands 3 feet from the source of exposure, receives an exposure of 16 R/min, and then moves to 6 feet from the source of exposure, what would be the new exposure rate according to the inverse square law? (in R/min)
4 R/min
Which image demonstrates a LOWER contrast?
B
Increasing the kVp will do which of the following?
Select one:
D. B and C
____________ will extend x-ray tube life.
Select one:
B. Warming up the tube after 2 hours of nonuse
If the intensity of an x-ray beam at 40 inches was 100 mR, what would the intensity be at 80 inches? (Units in mR)
25 mR
If the intensity of an x-ray beam at 100 cm was 50 mR, at what distance would the intensity be at 10 mR? (Round to the nearest whole number, units in cm)
224 cm
Which image demonstrates a LONG-scale of contrast?
B
The line focus principle describes the relationship between the:
Select one:
C. actual and effective focal spots
An optimal density exposure was made at 55 kVp and 5 mAs. In order to maintain radiographich density, what would the kVp be if the mAs was changed to 2.5 mAs? (Rounded to the nearest whole number, units in kVp)
63 kVp
Which image demonstrates a SHORT-scale of contrast?
A
What focal spot size is measured directly under the anode target?
Select one:
C. Effective focal spot
The target angle of rotating targets typically ranges from:
Select one:
A. 5 to 20°
Optimal density is achieved at an SID of 40 inches using 25 mAs. The SID must be increased to 72 inches. What adjustment in mAs is needed to maintain radiographic density? (Units in mAs)
81 mAs
Which image demonstrates a HIGHER contrast?
A
What causes the anode heel effect to occur?
Select one:
D. The angle of the target
Kilovoltage effects:
Select one:
C. Both
If 10 mAs produced optimal density at 40", what mAs would produce the same radiographic density at 20"? (Include your units as mAs)
2.5 mAs
An optimal density image was exposed at 20 inches. If the same density exposure was made at 40 inches using 100 mAs, what was the mAs used in the original exposure? (Units in mAs)
25 mAs
Diagnostic x-ray exposures range from:
Select one:
A. 30 to 150 kVp
Electrons can flow from cathode to anode or from anode to cathode during the x-ray exposure.
Select one:
True
False
False
A 15% increase in kilovoltage peak will have the same effect on radiographic density as doubling the mAs is known as the:
Select one:
D. 15% kVp rule
If an optimal density image was exposed using 10 mAs at 40 inches, what mAs would produce the same density if the distance was moved to 72 inches? (Round to the nearest whole number, units in mAs)
32 mAs
The quality of the CR latent image will remain the same for up to 6 hours after exposure.
Select one:
True
False
False
Increasing the thickness of the intensifying screen phosphor layer:
Select one:
B. Increases speed, decreases recorded detail, and decreases patient dose
List and SHORTLY expain 3 considerations with CR cassettes as explain in class or in the book.
Three considerations or things to remember about CR cassettes: they slowly receive background exposure and so they should be erased if not used within 48 hours, the latent image can fade and so they should be processed within 1 hour of exposure, and CR imaging plates have a 200 screen speed which is important to know for correct techniques and especially when converting techniques from film which has different screen speeds.
List 5 characteristics of good cassettes as explained in class or in the book.
Five good characteristics of cassettes include: light-proof, light weight, rigid, radiolucent, and absorb backscatter.
Direct exposure film uses 2 screens.
Select one:
True
False
False
The emulsion layer is filled with crystals made up of which molecules? (Choose all that apply)
Select one or more:
AgBr
NaCl
AgI
AuCOH
AgBr, AgI
Rare earth metals are more efficient phosphors in film screens than are calcium tungstate phosphors
Select one:
True
False
True
Film screen phosphors today are made of:
Select one:
C. Rare Earth metals
This image is an example of:
Select one:
B. Crossover
Fluorescence
Good
Phosphorescence
Bad
Match the letter to the appropriate term.
Emulsion layer– B,
Base– D
Adhesive layer– C
Supercoat– A
This formula is call the:
Select one:
A. mAs Converstion formula
The CR latent image consists of:
Select one:
D. Electrons trapped in the phosphor layer
What is the MAIN purpose for intensifying screens?
Select one:
B. Decrease patient exposure
In a screened cassette, direct exposure of x-rays exposes the film more than light produced by the intensifying screens
Select one:
True
False
False
What is the effect of the presence of a reflective layer within the intensifying screen?
Select one:
B. Increased speed, decreased recorded detail, and decreased patient dose
Define "screen speed"
Select one:
C. The capability of a screen to produce visible light
Is this image single emulsion or double emulsion film?
Select one:
A. Double emulsion film
Define "film speed"
Select one:
C. Degree to which the emulsion is sensitive to x-rays or light
Every type of darkroom safelight is safe for every kind of film
Select one:
True
False
False
Define "manifest image"
Select one:
C. image that exists on the film after exposure and processing
Define "latent image"
Select one:
C. image that exists after the film has been exposed but before processing
What is achieved when the color of light emitted by an intensifying screen matches the color of light a film responds to?
Select one:
C. Spectral matching
Which of the following is not a component of the CR IP?
Select one:
B. Emulsion layer
What is this layer called?
Select one:
D. Anticurl/antihalation layer
The front or tube side of radiographic cassettes should be made of a material that:
Select one:
D. Absorbs very little of the x-ray beam
Choose all of the following that affect screen speed:
Select one or more:
Size of phosphorus crystals
Presence of absorbing dyes in the phosphorus layer
Thickness of phosphorus layer
Presence of a reflective layer
Presence of an absorbing layer
Thickness of phosphorus layer, Size of phosphorus crystals, Presence of a reflective layer, Presence of an absorbing layer, Presence of absorbing dyes in the phosphorus layer
Answer the following question. (Do not include any units, for there are none)
25
Which of the following is not part of a CR reader unit?
Select one:
A. Developer tank
Spectral Sensitivity
Color of light which a particular film is most sensitive.
General blue or green sensitive.
Spectral Emission
Color of light produced by a particular intensifying screen.
Spectral Matching
Matching proper film color sensitivity to screen color emission.
Crossover
Refers to light that has been produced by an intensifying screen that exposes on the emulsion and then crossed ove the base layer of the film to expose the other emulsion.
Unique to double emulsion film.
Decreases recorded detail.
Halation
Image being recorded on the film by reflected light that exposes the emulsion a second time.
Causes light scatter, less contrast, image distortion, less clarity.
Luminescence
Emission of light from the screen when stimulated by radiation.
Two forms: fluorescence and phosphorescence.
Fluorescence
Ability of phosphors to emit visible light only while exposed to x-rays.
Phosphorescence
Occurs when screen phosphors continue to emit light after the x-ray exposure has stopped.
