Rad Science Final
How many alterations in the direction of the current flow occur in 0.10 second in a 60 Hz AC current? a. 60 b. 12 c. 120 d. 6
b. 12
The most common diagnostic radiography target angle is ____ degrees. a. 24 b. 12 c. 54 d. 45
b. 12
During fluoroscopy, the SOD on a fixed unit cannot be less than ____ inches. a. 40 b. 15 c. 20 d. 12
b. 15
A current of 2 amperes and a resistance of 8 ohms require what voltage in a circuit? a. 1/4 volt b. 16 volts c. 4 volts d. 1/16 volt
b. 16 volts
Nearly all types of x-ray equipment operate from an incoming line of a. 210 A. b. 210 V. c. 120 AC. d. 120 Hz.
b. 210 V.
Which examination does not exhibit an inherently large OID? a. lateral chest b. AP lumbar spine c. AP facial bones d. lateral cervical spine
b. AP lumbar spine
The value that indicates exposure to the IR with a cassette-less digital imaging system is the: a. exposure indicator b. DAP c. DQE d. none of the above
b. DAP
Following the detection of the light released from the phosphor layer, the signal is sent to the _____________ to allow the computer to process the data. a. digital-to-analog converter (DAC) b. analog-to-digital converter (ADC) c. light-to-computer device (LTC) d. none of the above
b. analog-to-digital converter (ADC)
The use of the line-focus principle causes a problem known as the ____ effect. a. space charge b. anode heel c. vacuum d. quantum mottle
b. anode heel
Secondary radiation energies are highest for which element? a. carbon b. barium c. oxygen d. hydrogen
b. barium
Increasing the kVp for an exposure will a. decrease the speed of electrons going from cathode to anode. b. cause the electrons to travel faster from cathode to anode. c. create an increase in the number of electrons traveling from cathode to anode. d. create a decrease in the number of electrons traveling from cathode to anode.
b. cause the electrons to travel faster from cathode to anode
Current is a. time/charge. b. charge/time. c. (charge)(time). d. charge/time2.
b. charge/time.
Cameron describes changing the kVp has similar to changing the ______of visible light. a. brightness b. color c. direction d. focus
b. color
Flux gain a. improves image resolution due to the small penumbra created by the output phosphor crystals. b. deals with the gain resulting from the conversion of light at the output phosphor. c. is directly related to the input phosphor conversion efficiency. d. all of the above
b. deals with the gain resulting from the conversion of light at the output phosphor.
As the matrix size decreases, the spatial resolution: a. increases b. decreases c. remains the same d. none of the above
b. decreases
As the operating speed class of a digital system decreases, the image noise_______________ and the patient exposure ________________. a. increases; increases b. decreases; decreases c. increases; decreases d. decreases; increases
b. decreases; decreases
The density maintenance formula is a a. reciprocity law. b. direct square law. c. 15 percent rule. d. inverse square law
b. direct square law.
The length of the exposure time (S) for a radiograph, is used to primarily control a. radiographic image density. b. motion. c. patient dose. d. image contrast.
b. motion.
The dynamic range of a digital imaging system is ____________ than that of a film-screen system. a. much less b. much greater c. approximately the same d. a little bit greater
b. much greater
The focusing cup has a/an ____ charge. a. atomic b. negative c. neutral d. positive
b. negative
Primary (diagnostic) workstation displays are used for: a. viewing the image for the first time b. official image interpretation c. viewing the digital image at the radiographer's console d. all of the above
b. official image interpretation
During which interaction with matter is the x-ray photon converted to matter in the form of two electrons? a. Compton scattering b. pair production c. photoelectric absorption d. coherent scattering
b. pair production
During fluoroscopy, the principal source of radiation exposure to personnel in the room is the a. radiologist. b. patient. c. image detector. d. fluoroscopy x-ray tube.
b. patient.
Poor resolution is caused by unacceptable levels of a. density. b. penumbra. c. contrast. d. umbra.
b. penumbra.
In diagnostic radiology, radiographic image contrast is principally due to the predominance of a. Bremsstrahlung interactions. b. photoelectric interactions. c. Compton interactions. d. photodisintegration interactions
b. photoelectric interactions.
Performing a routine chest radiograph in the anterior-posterior (AP) projection will a. decrease breast exposure. b. produce improved resolution of the thoracic spine. c. decrease heart size on the image. d. demonstrate higher resolution of the anterior ribs.
b. produce improved resolution of the thoracic spine.
Unwanted radiographic image densities caused predominantly by scattered photons is called a. photoelectric fog. b. radiation fog. c. base fog. d. chemical fog.
b. radiation fog
During Compton scattering, the incident photon energy is divided between the a. incident photon and the scattered photon. b. recoil electron and the scattered photon. c. incident photon and the recoil electron. d. recoil electron and the photoelectron.
b. recoil electron and the scattered photon.
This part of the plate will direct light in the right direction when the plate is read. a. plate reader b. reflective layer c. photostimulable phosphor plate d. barium fluorohalide
b. reflective layer
Resistance is a. the location of storage of electrons. b. the opposition to the flow of electrons. c. the opposition to the generation of electromotive force. d. measured in amperes.
b. the opposition to the flow of electrons.
The placement of several CCD detectors close together to form a larger detector is called: a. roofing b. tiling c. butting d. none of the above
b. tiling
A filament may break due to a. deposition. b. vaporization. c. evaporation. d. increased sensitivity.
b. vaporization.
Electric potential is measured in a. coulombs. b. volts. c. ohms. d. joules.
b. volts.
Melting of the anode commonly occurs a. when the unit is not warmed up properly. b. when the stator fails and the rotor ceases to turn. c. when the kilovoltage is too high. d. with extended use.
b. when the stator fails and the rotor ceases to turn.
Pitting of the anode commonly occurs a. when the kilovoltage is too high. b. with extended use. c. when the anode is off-focus. d. when the unit is not warmed up properly.
b. with extended use.
If 20 volts of potential difference causes a current of 5 amperes to flow in a parallel circuit, the resistance produced is a. 4 ohms. b. 1/4 ohm. c. 100 ohms. d. 1/100 ohm.
a. 4 ohms.
Noise in the digital image is due to: a. B and C b. quantum noise c. electronic noise d. patient noise
a. B and C
__________ is the standard format for digital medical images. a. DICOM b. PACS c. teleradiology d. RIS
a. DICOM
The cassette-less digital imaging system is also referred to as: a. DR b. CR c. cassette-based d. all of the above
a. DR
X-ray beam quality is numerically represented by the a. HVL. b. SOD. c. OID. d. mAs.
a. HVL.
All of the following are true of the fluoroscopic lead apron drape EXCEPT: a. It covers the Bucky slot in the table. b. It is designed to absorb a large percentage of patient scatter. c. It should be 0.25 mm Pb equivalent. d. It may be detached for specific cases.
a. It covers the Bucky slot in the table
The ideal expression of digital detector image resolution is the: a. MTF b. Nyquist frequency c. LSR d. DQE
a. MTF
The electronic components of cassette-less systems that is configured in a network of detector elements is the: a. TFT b. CCD c. photoconductor d. scintillator
a. TFT
The types of target interaction that occur in the production of x-ray photons in the diagnostic range are dependent upon the a. incident electron kinetic energy. b. nuclear binding energy. c. incident electron potential energy. d. band gap of the valence electrons.
a. incident electron kinetic energy.
This represents the exposure level to the PSP plate: a. exposure indicator b. DAP c. DQE d. none of the above
a. exposure indicator
Automatic exposure control (AEC) technology determines a. exposure time. b. patient thickness. c. kVp. d. mA.
a. exposure time.
Mobile fluoroscopic systems are different from fixed systems in that they a. have a minimum SOD of 12 inches. b. do not use video displays. c. do not have a primary barrier. d. have separate fluoroscopy and radiographic tubes.
a. have a minimum SOD of 12 inches.
Tungsten is the metal of choice for the source of x-ray photons because of its a. high atomic number. b. low melting point. c. low mass number. d. all of the above
a. high atomic number.
The incoming line current is supplied from the power company to the hospital a. in the form of a three-phase power cycle. b. at approximately 60 volts. c. in the form of a single-phase power cycle. d. as a direct current.
a. in the form of a three-phase power cycle.
Electrons traveling from the cathode filament to the anode are called a. incident electrons. b. primary electrons. c. secondary electrons. d. scatter electrons
a. incident electrons.
When kVp increases, photoelectric effect a. increases greatly b. decreases greatly c. increases proportionally d. decreases proportionally
a. increases greatly
The resistance in a wire decreases as its diameter a. increases. b. decreases. c. remains the same. d. none of the above
a. increases.
The most common diagnostic radiography target angle is ____ degrees. a. 54 b. 45 c. 12 d. 24
c. 12
How many alterations in the direction of the current flow occur per second in a 60 Hz AC current? a. 90 b. 60 c. 120 d. 20
c. 120
If the peak kVp is 110, the average keV energy of the beam would be a. 66-77 keV. b. 110 keV. c. 33-44 keV. d. 12-24 keV
c. 33-44 keV.
If 20 volts of potential difference causes a current of 5 amperes, the resistance produced is a. 1/4 ohm. b. 1/100 ohm. c. 4 ohms. d. 100 ohms.
c. 4 ohms.
A radiograph is taken at 400 mA, 55 ms, 95 kVp. A second image could be taken to increase differential absorption (possibly increase contrast) at a. 400 mA, 0.055 sec, 110 kVp. b. 500 mA, 4 ms, 95 kVp. c. 400 mA, 0.110 sec, 80 kVp. d. 600 mA, 0.083 sec, 92 kVp.
c. 400 mA, 0.110 sec, 80 kVp
If 10 coulombs pass a point in 2 seconds, the current is a. 0.20 amp. b. 20 amps. c. 5 amps. d. 200 amps.
c. 5 amps.
Which of the following sets of exposure factors would best control involuntary motion? a. 300 mA, 30 ms b. 200 mA, 0.045 sec c. 500 mA, 18 ms d. 100 mA, 0.09 sec
c. 500 mA, 18 ms
If 1 coulomb is equal to 6.3 ´ 1018 electron charges, how many electrons flow from cathode to anode in 1 second? a. 6.3 ´ 10^4 b. 6.3 ´ 10^18 c. 6.3 ´ 10^8 d. 6,300
c. 6.3 ´ 10^8
Digital imaging preprocessing includes: a. rescaling b. histogram analysis c. A and B d. none of the above
c. A and B
All of the following are true of the substance glucose (C6H12O6) EXCEPT: a. The smallest subdivision of this molecule is glucose. b. It is a compound. c. It may be broken down into one atom of glucose. d. It consists of three elements.
c. It may be broken down into one atom of glucose.
Which atomic shell possesses the highest binding energy? a. M b. All atomic shells possess the same binding energy. c. K d. L
c. K
Which energy-level electrons possess the highest total energy? a. M b. L c. N d. K
c. N
__________ allows for the acquisition, display, and storage of digital images. a. DICOM b. RIS c. PACS d. teleradiology
c. PACS
Resolution is improved when a. OID increases. b. SID decreases. c. SID increases. d. the receptor is angled.
c. SID increases.
All of the following are true of electromagnetic energies EXCEPT: a. They are illustrated as sinusoidal waves. b. They possess both wave and particle characteristics. c. The relationship between frequency and wavelength is direct and proportional. d. They are arranged in an orderly spectrum according to frequency and wavelength.
c. The relationship between frequency and wavelength is direct and proportional.
In general radiography, quantum noise is a. filtered out of images. b. a recorded detail parameter. c. a function of mAs and kVp. d. designed into the receptor specifications.
c. a function of mAs and kVp.
When an electron from an outer shell fills a vacancy in an inner shell, a. the total energy of the electron increases. b. the electron increases its mass. c. a photon is released. d. all of the above
c. a photon is released.
The physical area of the focal track affected by the electron beam is the a. effective focal spot. b. effective focal track. c. actual focal spot. d. all of the above
c. actual focal spot.
In which process is matter converted back to energy? a. photodisintegration b. nuclear reaction c. annihilation reaction d. Compton scatter
c. annihilation reaction
Milliamperage-second (mAs) directly affects all of the following EXCEPT a. x-ray output. b. beam intensity. c. beam quality. d. beam quantity
c. beam quality.
What type of radiation is composed of photons not produced at the actual focal spot? a. off-focus b. extrafocal c. both a and b d. primary
c. both a and b
The primary ____ occurs from the acceleration and focusing of the electron beam. a. phosphorescence b. minification c. brightness gain d. magnification
c. brightness gain
All of the following choices are considered good metallic electrical conductors EXCEPT a. copper. b. gold. c. carbon. d. silver.
c. carbon.
The part of a PSP plate that gives some rigidity to the plate is the: a. conductive layer b. structured phosphor layer c. support layer d. turbid phosphor layer
c. support layer
Photoemissive materials absorb ____ and emit ____. a. x-ray photons; light photons b. light photons; x-ray photons c. x-ray photons; electrons d. light photons; electrons
d. light photons; electrons
Compton scattering occurs when an incident x-ray photon interacts with a ____ electron a. loosely bound inner-shell b. tightly bound inner-shell c. tightly bound outer-shell d. loosely bound outer-shell
d. loosely bound outer-shell
The best method for controlling motion when the patient is unable to cooperate is to a. increase kVp. b. maintain mAs, while decreasing mA. c. decrease kVp. d. maintain mAs, while decreasing time.
d. maintain mAs, while decreasing time.
Which measures the accuracy of an image compared to the original object on a scale of 0 to 1? a. line spread function b. noise reduction function c. point spread function d. modulation transfer function
d. modulation transfer function
In a battery circuit with several resistors of different values connected in series, a. the voltage drop is the same across all the resistors. b. the current through each resistor is different. c. the power dissipated through each resistor is the same. d. none of the above
d. none of the above
The part of the reader that consists of a laser light, filters, and beam-shaping devices is the __________. a. photostimulable luminescence b. drive mechanism c. photodetector d. optical system
d. optical system
Where is the stator of the anode induction motor located? a. inside the glass envelope and inside the rotor b. inside the glass envelope but outside the rotor c. outside the glass envelope but inside the rotor d. outside the glass envelope and outside the rotor
d. outside the glass envelope and outside the rotor
Proper alignment is achieved when the central ray is ____ to the part and ____ to the image receptor. a. perpendicular; parallel b. parallel; parallel c. parallel; perpendicular d. perpendicular; perpendicular
d. perpendicular; perpendicular
Amorphous selenium is used as the: a. photoconductor for indirect capture cassette-less digital imaging b. photodetector for indirect capture cassette-less digital imaging c. photodetector for direct capture cassette-less digital imaging d. photoconductor for direct capture cassette-less digital imaging
d. photoconductor for direct capture cassette-less digital imaging
The part of the reader that senses the light released from the PSP plate is the: a. photostimulable luminescence b. drive mechanism c. optical system d. photodetector
d. photodetector
The atomic number is the number of ____ contained in the nucleus. a. electrons b. neutrons c. positrons d. protons
d. protons
Fluoroscopy is the domain of the a. radiation physicist. b. radiographer. c. quality control technologist. d. radiologist.
d. radiologist.
The electron dislodged during Compton scattering is called the a. incident electron. b. secondary electron. c. photoelectron. d. recoil electron
d. recoil electron
The rate at which sampling occurs is the: a. sampling pitch b. sampling rate c. bit depth d. sampling frequency
d. sampling frequency
When x-ray photons interact with matter and change direction, the process is called a. absorption. b. interpolation. c. extrapolation. d. scatter
d. scatter
When the sampling frequency is less than the Nyquist value, a. the Nyquist value must be altered. b. aliasing is eliminated. c. patient dose must increase. d. the Moire effect can occur.
d. the Moire effect can occur.
The energy of a characteristic photon is a. the sum of the binding energy of the outer and inner shells between which the electron dropped. b. equal to the binding energy of the entering electron. c. equal to the binding energy of the exiting electron. d. the difference between the binding energy of the outer and inner shells between which the electron dropped.
d. the difference between the binding energy of the outer and inner shells between which the electron dropped.
The energy of a bremsstrahlung photon is a. equal to the kinetic energy of the exiting electron. b. equal to the kinetic energy of the entering electron. c. the sum of the entering and exiting kinetic energy of the incident electron. d. the difference between the entering and exiting kinetic energy of the incoming electron.
d. the difference between the entering and exiting kinetic energy of the incoming electron.
What percentage of target interaction results in the production of x-ray photons? a. 1 percent b. 50 percent c. 100 percent d. 99 percent
a. 1 percent
If the total resistance in a circuit is 9 ohms and the total voltage is 3 volts, the current is a. 1/3 ampere. b. 3 amperes. c. 27 amperes. d. 1/27 ampere.
a. 1/3 ampere.
A 100 W light bulb with an amperage of 0.91 A is operating at a potential difference of a. 110 volts. b. 100 volts. c. 11 kilovolts. d. 110 ohms.
a. 110 volts.
The radiologist should have a _______ display monitor for interpretation of general radiographic studies, whereas a ________ monitor is needed for digital mammograms. a. 2 Mp; 5 Mp b. 5 Mp; 2 Mp c. 2 Mp; 1 Mp d. 1 Mp; 2 Mp
a. 2 Mp; 5 Mp
The maximum number of electrons found in any energy level (shell) at any point in time is calculated by the formula a. 2n^2. b. N = amu x Z. c. V= I x R. d. W = F x D.
a. 2n^2.
Which radiograph exhibits the best detail? a. a PA chest radiograph for evaluation of the heart at 72 in. b. an AP chest radiograph for evaluation of the heart at 72 in. c. a PA chest radiograph for evaluation of the heart at 40 in. d. an AP chest radiograph for evaluation of the heart at 40 in.
a. a PA chest radiograph for evaluation of the heart at 72 in.
During the photoelectric interaction, as an electron transfers from an outer shell to a vacant inner shell,energy is released in the form of a. a characteristic photon. b. an incident electron. c. a gamma photon. d. a primary radiation
a. a characteristic photon.
During a characteristic interaction, the dropping of a higher-energy state electron into a lower-energy state "hole" results in the emission of a. a photon of electromagnetic energy. b. a gamma photon. c. a low-energy electron. d. a high-energy electron.
a. a photon of electromagnetic energy.
The function of the cathode is to produce a. a thermionic cloud. b. an electrical connection to the rectifier. c. a grounding effect. d. a focal point.
a. a thermionic cloud.
The physical area of a rotating anode focal track, affected by the cathode electron beam, is the a. actual focal spot. b. effective focal spot. c. effective focal track. d. projected focal track.
a. actual focal spot.
Europium serves as: a. an activator for the phosphor b. the protective layer c. the reflective part of the PSP plate d. none of the above
a. an activator for the phosphor
The orderly arrangement of elements in the periodic table is based upon a. atomic number. b. neutron number. c. mass number. d. atomic weights.
a. atomic number.
At what point in the x-ray circuit is the rectification circuit located? a. between the step-up transformer and the x-ray tube b. between the semiconductors and the valve tubes c. between the step-down transformer and the rheostat d. between the thermionic diode tubes and the x-ray machines
a. between the step-up transformer and the x-ray tube
An ampere is a. coulomb/sec. b. (volt)(ohm). c. ohm/volt. d. (coulomb)(sec).
a. coulomb/sec.
If the distance between two electrical charges is doubled, the force between them is a. decreased by 75%. b. decreased by ½. c. Quadrupled. d. Doubled.
a. decreased by 75%.
Adjustments in kVp should be used to control a. differential absorption b. density. c. distance. d. detail.
a. differential absorption
Fluoroscopy is a ____ x-ray examination. a. dynamic, real-time b. static c. therapeutic d. all of the above
a. dynamic, real-time
The area of the focal spot that is projected out of the tube toward the object being radiographed is the a. effective focal spot. b. effective focal track. c. actual focal spot. d. all of the above
a. effective focal spot.
Electrostatic lenses are used to accelerate and focus a. electrons. b. scattered photons. c. light photons. d. x-ray photons.
a. electrons.
Which of the following cassette-less digital image receptors does not use a network of TFTs? a. indirect capture with CCD b. indirect capture with amorphous silicon photodetector c. direct capture with amorphous selenium photoconductor d. none of the above use TFTs
a. indirect capture with CCD
The transfer of the incident electrons' kinetic energy to the outer-shell electrons causing vibration of the outer-shell electron results in the emission of a. infrared radiation. b. light. c. sound. d. ultraviolet radiation.
a. infrared radiation.
Electric insulators a. inhibit movement of electrical charge. b. convert electrical energy into heat. c. permit movement of electrical charge. d. consist of materials like silicon.
a. inhibit movement of electrical charge.
During photoelectric absorption, a/an ____ shell electron is ejected. a. inner b.middle c.outerd. all of the above
a. inner
During fluoroscopic image intensification, the primary x-ray beam exits the patient and strikes the ____ of the image intensifier. a. input screen b. electrostatic lenses c. photocathode d. output screen
a. input screen
The factors that directly affect x-ray quality are a. kVp and beam filtration. b. mAs and distance. c. focal spot size and anode angle. d. filtration and mAs.
a. kVp and beam filtration.
Examinations of body parts with a large inherent OID warrant a ____ whenever possible. a. large SID b. small SOD c. small SID d. large focal spot
a. large SID
In which element are the inner-shell electrons more tightly bound to the nucleus? a. lead (Z = 82) b. chromium (Z = 24) c. tungsten (Z = 74) d. mercury (Z = 80)
a. lead (Z = 82)
When an electric current flows through a wire with resistance, energy is a. liberated as heat. b. liberated as light. c. liberated as x-rays. d. absorbed as heat.
a. liberated as heat.
Undesirable fluctuations in the brightness of an image is: a. noise b. DAP c. DQE d. contrast
a. noise
When an x-ray photon with a slightly greater energy than the binding energy of the inner-shell electron interacts with that inner-shell electron, the following interaction results: a. photoelectric absorption b. characteristic radiation c. Compton scattering d. coherent scattering
a. photoelectric absorption
Which of the following interactions has a significant impact on the x-ray image? a. photoelectric absorption b. coherent scatter c. pair production d. photodisintegration
a. photoelectric absorption
During photoelectric absorption, the ejected electron is called a/an a. photoelectron. b. nuclear electron. c. incident electron. d. characteristic electron
a. photoelectron
In a fluoroscopy system, the x-ray tube and image receptor must be interlocked in order to enable fluoroscopy. This classifies the image receptor as the a. primary barrier. b. principal barrier. c. scatter barrier. d. secondary barrier.
a. primary barrier.
The nuclear particles that distinguish one element from another are the a. protons. b. gamma particles. c. neutrons. d. beta particles.
a. protons.
Groups of the periodic table a. represent elements with the same outer electron configuration. b. are horizontal. c. represent elements with the same atomic density. d. none of the above
a. represent elements with the same outer electron configuration.
A charge would lose most of its energy when it passes through a a. resistor. b. battery. c. generator. d. all of the above
a. resistor.
The function of the stator and rotor assembly is to a. rotate the anode. b. insulate the anode. c. create a vacuum. d. disrupt the electromagnets of the induction motor.
a. rotate the anode.
The Nyquist frequency is a. sampling a minimum of twice per cycle. b. unique to radiography. c. important in analog imaging. d. related to involuntary motion.
a. sampling a minimum of twice per cycle.
All of the following are energy forms EXCEPT a. sound. b. thermal. c. electrical. d. nuclear.
a. sound.
During coherent scattering, the scattered photon possesses ____ as the incident photon a. the same energy, the same frequency, and the same wavelength b. the same energy, a different frequency, and the same wavelength c. a different energy, the same frequency, and the same wavelength d. the same energy, the same frequency, and a different wavelength
a. the same energy, the same frequency, and the same wavelength
One half of the Nyquist frequency is equal to: a. the spatial resolution of a digital system b. the contrast resolution of a digital system c. the amount of noise in a digital system d. none of the above
a. the spatial resolution of a digital system
When the x-ray emission spectra between single- and three-phase generators are compared, a. three-phase beams would have a higher average energy. b. less exposure would be required for the same part thickness, using-single phase. c. the keV of the characteristic spike would be significantly less with the single-phase generator. d. single-phase beams would be more intense.
a. three-phase beams would have a higher average energy.
When radiographing a wedge-shaped anatomical structure such as the femur, the thicker portion of the anatomy should be positioned a. under the cathode end of the tube. b. off center laterally to negate the heel effect. c. under the anode side of the tube. d. in the exact center of the beam. as it is most intense in the center.
a. under the cathode end of the tube.
When full-wave rectification is applied to three-phase current, a ____ ripple is produced. a. voltage b. current c. double d. star
a. voltage
The product of tube current and exposure time is equal to a. x-ray beam quantity. b. kVp. c. the HVL. d. x-ray beam quality.
a. x-ray beam quantity.
The input screen absorbs ____ and emits ____. a. x-ray photons; light photons b. electrons; x-ray photons c. light photons; x-ray photons d. x-ray photons; electrons
a. x-ray photons; light photons
Carestream and Agfa use exposure indicators that vary ____________ with changes in exposure to the PSP plate; Fuji and Konica Agfa use exposure indicators that vary ____________ with changes in exposure to the PSP plate: a. indirectly; indirectly b. directly; indirectly c. directly; directly d. indirectly; directly
b. directly; indirectly
An increase in kVp by 15 percent will cause an approximate ____ in the exposure to the image receptor. a. 15 percent increase b. doubling c. quadrupling d. tripling
b. doubling
The useful imaging area of the digital receptor is the: a. detector element (DEL) b. field of view (FOV) c. thin-film transistor (TFT) d. none of the above
b. field of view (FOV)
The prime factors include all of the following EXCEPT a. mAs. b. filtration. c. distance. d. kVp.
b. filtration
Factors affecting recorded detail include a. mAs. b. focal spot size. c. radiographic grids. d. kVp.
b. focal spot size.
Increasing the energy of an incident electron will result in the production of an x-ray photon with a. less energy. b. greater energy. c. greater charge. d. greater velocity
b. greater energy.
During a characteristic interaction, the kinetic energy of the incident electron must be ____ the electron it knocks from its orbit. a. characteristic of b. greater than or equal to c. less than that of d. proportional to that of
b. greater than or equal to
The ____ the SID, the ____ the magnification. a. greater; larger b. greater; smaller c. lesser; smaller d. SID has no effect on magnification.
b. greater; smaller
Tungsten is the metal of choice for the source of x-ray photons because of its a. low melting point. b. high atomic number. c. low cost. d. low mass number.
b. high atomic number.
Filament and target materials are chosen for their a. ability to vaporize easily. b. high melting points. c. high boiling points. d. low melting points.
b. high melting points.
The incoming line current is supplied a. in the form of a single-phase power cycle. b. in the form of a three-phase power cycle. c. at approximately 60 volts. d. as a direct current.
b. in the form of a three-phase power cycle.
The most common solution for quantum mottle is to a. decrease the fluoro tube mA. b. increase the fluoro tube mA. c. decrease the efficiency of the input screen. d. decrease the efficiency of the flux gain.
b. increase the fluoro tube mA.
In digital imaging systems , increasing sampling frequency of the data a. decreases dose. b. increases image fidelity. c. decreases MTF. d. increases dose.
b. increases image fidelity.
As the mA doubles, the number of electrons flowing from cathode to anode a. increases by 50%. b. increases twofold. c. increases fourfold. d. decreases twofold
b. increases twofold
The incidence of the photoelectric effect increases with a. increasing kilovoltage. b. increasing atomic number of the absorber. c. photon energies above 1.02 mMeV. d. decreasing x-ray wavelength
b. increasing atomic number of the absorber.
The photocathode absorbs ____ and emits ____. a. electrons; light photons b. light photons; electrons c. x-ray photons; light photons d. light photons; x-ray photons
b. light photons; electrons
The unit of resolution in film/screen imaging is a. the DEL size. b. line pairs per millimeter. c. the Curie. d. pixel size.
b. line pairs per millimeter.
Scatter control is ___________ important with digital imaging as compared with filmscreen. a. less b. more c. the same d. none of the above
b. more
Insulation of the high-voltage components of the tube and absorption of the heat produced by x-ray production is achieved through the use of a. a small fan. b. a stator. c. dielectric oil. d. a vacuum.
c. dielectric oil.
The current flow from a dry cell battery source would be a. variable current. b. oscillating current. c. direct current. d. alternating current.
c. direct current.
Which of the following occurs when the tube or the image receptor is not properly aligned? a. magnification b. foreshortening c. elongation d. minification
c. elongation
The range of exposures that produce acceptable information to be used in image formation is: a. exposure range b. dynamic range c. exposure latitude d. all of the above
c. exposure latitude
Radiographic rooms equipped with a tilting table are primarily designed for performing ____ procedures. a. extremity b. surgical x-ray c. fluoroscopic d. C-arm
c. fluoroscopic
As the angle of deflection is increased from 0° to 180°, a. greater energy is imparted to the scattered photon. b. all energy is imparted to the incident photon. c. greater energy is imparted to the recoil electron. d. less energy is imparted to the recoil electron.
c. greater energy is imparted to the recoil electron.
When tissue density increases, attenuation a. decreases greatly b. increases greatly c. increases proportionally
c. increases proportionally
The primary factor controlling x-ray beam quantity is determined by a. filtration. b. kVp. c. mAs. d. distance
c. mAs.
Size distortion in radiography can be ____ only. a. minimization b. foreshortening c. magnification d. elongation
c. magnification
The sum of protons and neutrons in a nucleus is called the a. quantum number. b. electron number. c. mass number. d. atomic weight.
c. mass number.
An electron is ____ charged and has a mass of ____ amu(s). a. neutral; 1 b. positively; 0.000548 c. negatively; 0.000548 d. positively; 1
c. negatively; 0.000548
At the end of the characteristic cascade, the ____ shell is missing an electron. a. K b. characteristic c. outermost d. innermost
c. outermost
Part of the direct-capture cassette-less system, the __________ absorbs x-rays and produces an electric signal: a. CCD b. TFT c. photoconductor d. scintillator
c. photoconductor
Amorphous silicon is used as the: a. photoconductor for indirect capture cassette-less digital imaging b. photodetector for direct capture cassette-less digital imaging c. photodetector for indirect capture cassette-less digital imaging d. photoconductor for direct capture cassette-less digital imaging
c. photodetector for indirect capture cassette-less digital imaging
The type of image receptor used in cassette-based digital systems is the: a. reflective layer b. barium fluorohalide c. photostimulable phosphor plate d. plate reader
c. photostimulable phosphor plate
The factors that affect x-ray emission under the direct control of the radiographer are called the ____factors. a. quality b. principal c. prime d. quantity
c. prime
When the position of the patient is reversed, the direction of the tube angle must be ____ to maintain the relationship. a. maintained b. decreased c. reversed d. increased
c. reversed
The photon that exits the atom after a Compton scattering is called the Compton a. scattered electron. b. recoil electron. c. scattered photon. d. photoelectron
c. scattered photon.
The component of cassette-less digital imaging systems that absorbs x-rays and produces light is the: a. CCD b. photoconductor c. scintillator d. TFT
c. scintillator
Distortion is a misrepresentation of a. detail. b. shape only. c. size and shape. d. size only.
c. size and shape.
As more and more electrons build up in the area of the filament, their negative charges oppose the emission of additional electrons. This phenomenon is known as a. biased cloud formation. b. thermionic emission. c. space charge effect. d. current saturation.
c. space charge effect.
All of the following are part of the cathode assembly EXCEPT a. associated wiring. b. filament. c. stator. d. focusing cup.
c. stator.
When comparing the x-ray emission spectrum between beams produced at 70 kVp and 110 kVp a. the 70 kVp beam would demonstrate less brems and a higher characteristic spike. b. the 70 kVp beam would demonstrate an equal amount of brems and characteristic radiation. c. the 110 kVp beam would demonstrate more brems and a higher characteristic spike. d. the 110 kVp beam would demonstrate less brems and a higher characteristic spike.
c. the 110 kVp beam would demonstrate more brems and a higher characteristic spike.
Histogram analysis compares the histogram with histograms specific to: a. the computer monitor b. the x-ray equipment c. the anatomic part being imaged d. the patient data
c. the anatomic part being imaged
In a parallel circuit, a. Ohm's law does not apply. b. total current flow is equal across its parallel branches. c. the voltage is equal across all branches of the circuit. d. as more resistors are added total resistance increases.
c. the voltage is equal across all branches of the circuit.
The electrical device used to adjust the mA selection is the a. autotransformer. b. switch. c. variable resistor. d. stator.
c. variable resistor.
The edge distortion problem in image intensification tubes is called a. minification. b. magnification. c. vignetting. d. all of the above
c. vignetting.
Melting of the anode commonly occurs a. with extended use. b. when the kilovoltage is too high. c. when the stator fails and the rotor ceases to turn. d. when the unit is not warmed up properly.
c. when the stator fails and the rotor ceases to turn.
Fluoroscopic mA range is commonly ____ mA. a. 100 to 500 b. 5.0 to 10.0 c. 10.0 to 100 d. 0.5 to 5.0
d. 0.5 to 5.0
Methods to reduce fluoroscopic radiation exposure include: 1. automatic brightness control 2. Bucky tray slot cover 3. switching to magnification imaging 4. fluoroscopic lead apron drape 5. dead-man type fluoroscopy switch 6. LIH 7. increase the SID 8. decrease the SOD 9. decrease the OID a. 2, 3, 4, 6 and 7 b. 1, 2, 4, 7 and 9 c. 1, 4, 5, 6, 8 and 9 d. 1, 2, 4, 5, 6 and 9
d. 1, 2, 4, 5, 6 and 9
The K shell can hold a maximum of ____ electrons. a. 6 b. 1 c. 8 d. 2
d. 2
A three-phase, rectified current produces a voltage ripple of ____ pulses per Hz. a. 24 b. 9 c. 3 d. 6
d. 6
Digital imaging quality control focuses on: a. the display monitors b. the viewing environment c. the radiologist's comfort d. A and B
d. A and B
Sampling pitch is: a. the distance between laser beam positions during sampling b. the distance between adjacent detector elements c. the length of time it takes to take all samples d. A and B
d. A and B
Indirect capture cassette-less digital imaging systems use: a. charge-coupled devices b. photoconductors and TFT arrays c. scintillator and TFT array d. A and C
d. A and C
Part of a cassette-less indirect capture system, the light-sensitive device that is commonly found in digital cameras is the: a. scintillator b. photoconductor c. TFT d. CCD
d. CCD
The unit of mass is the a. m/sec. b. mm. c. cc. d. kg.
d. kg.
In the human body, ____ is the predominant interaction through most of the diagnostic x-ray range. a. coherent scatter b. photodisintegration c. photoelectric interactions d. Compton scattering
d. Compton scattering
Which of the following interactions has a significant impact on the x-ray image? a. pair production b. coherent scatter c. photodisintegration d. Compton scattering
d. Compton scattering
Which of the following interactions with matter results in a radiograph with a loss of radiographic image contrast? a. photoelectric interactions b. coherent scatter c. Compton scattering d. photodisintegration
d. Compton scattering
As the spatial frequency of objects increases, a. MTF increases. b. MTF computes to a value of 1. c. MTF increases proportionally. d. MTF decreases.
d. MTF decreases.
A photoelectron a. is matter and possesses energy. b. typically travels 1-2 mm in soft tissue. c. is capable of creating biological changes. d. all of the above
d. all of the above
An interaction that occurs between very low energy x-ray photons and matter is called ____ scatter. a. coherent b. classical c. unmodified d. all of the above
d. all of the above
Digital fluoroscopy is typically a. a progressive, pulsed fluoroscopic exposure. b. capable of producing higher contrast images. c. capable of 256 shades of gray through 8-bit processing. d. all of the above
d. all of the above
During the process of attenuation, the x-ray photon may interact with a. the nucleus. b. the entire atom. c. an orbital electron. d. all of the above
d. all of the above
During the process of attenuation, x-ray photons in the beam a. reduce in number. b. lose energy. c. interact. d. all of the above
d. all of the above
Flat panel digital detectors used for fluoroscopy use a. amorphous silicon as the digital detector. b. a cesium iodide scintillator. c. TFT technology. d. all of the above
d. all of the above
Fluoroscopic resolution with image intensification will vary according to a. minification gain. b. electrostatic focal point. c. input and output screen diameter. d. all of the above
d. all of the above
If uranium were used to produce x-radiation, rather than tungsten, a. the K-shell binding energy would be greater than with tungsten. b. the intensity of brems production would be greater. c. the energy of characteristic photons would be greater than with tungsten. d. all of the above
d. all of the above
Penumbra decreases as a. focal spot decreases. b. OID decreases. c. SID increases. d. all of the above
d. all of the above
Present-day AEC technology utilizes a. ionization chamber technology. b. minimum reaction times as short as 1 ms. c. a pre-detector AEC chamber position. d. all of the above
d. all of the above
Recorded detail is a. the degree of geometric sharpness. b. definition. c. the accuracy of the structural lines actually recorded in the radiographic image. d. all of the above
d. all of the above
The diagnostic x-ray range is approximately a. 10 to 1,200 mA. b. 0.001 to 10 seconds. c. 25 to 150 kVp. d. all of the above
d. all of the above
The emission spectrum of an x-ray beam from a tungsten anode consists of a. a characteristic spike at 69 keV. b. a significant portion due to bremsstrahlung interactions. c. a mixture of brems and characteristic interactions. d. all of the above
d. all of the above
The problem of off-focus radiation a. is particularly important with digital detectors. b. distorts the digital histogram. c. may result in suboptimum digital images. d. all of the above
d. all of the above
Total brightness gain is a. a measure of the increase in image intensity. b. determined by minification gain. c. determined by flux gain. d. all of the above
d. all of the above
When compared to single-phase electrical current, three-phase power a. permits shorter exposures. b. produces 360 pulses per second. c. produces less voltage ripple. d. all of the above
d. all of the above
Which condition is needed to produce an x-ray? a. a source of electrons b. a vacuum c. a large potential difference d. all of the above
d. all of the above
Characteristic interactions may occur only when the incident electron interacts with a. an outer-shell electron. b. the force field of the nucleus. c. protons within the nucleus. d. an inner-shell electron.
d. an inner-shell electron.
If an electron is gained or lost from an atom, that atom becomes a. unstable. b. a new element. c. an isotope. d. an ion.
d. an ion.
X-ray photon production occurs at the a. stator. b. filament. c. cathode. d. anode.
d. anode.
When an x-ray photon passes through matter, it undergoes a process called a. induction. b. filtration. c. resonance d. attenuation.
d. attenuation.
The factors that directly affect x-ray quantity are a. mA. b. time (S). c. filtration. d. both a and b
d. both a and b
X-ray tube angulations inherently a. require radiographic grids. b. change the SID. c. introduce magnification to some degree. d. both b and c
d. both b and c
X-rays are characterized as a. charged particles. b. electromagnetic waves of short wavelength. c. electromagnetic waves with high frequencies. d. both b and c
d. both b and c
The actual focal spot is controlled by the a. thickness of the anode disc. b. anode rotation speed. c. angle of the cathode focusing cup. d. length of the filament.
d. length of the filament.
The part of a PSP plate that reduces and carries away static electricity is the: a. turbid phosphor layer b. structured phosphor layer c. support layer d. conductive layer
d. conductive layer
The milliampere(mA) is a unit of a. voltage. b. EMF. c. potential difference. d. current.
d. current.
Isotopes have ____ mass numbers and ____ atomic numbers. a. different; different b. the same; the same c. the same; different d. different; the same
d. different; the same
The relationship between mAs and exposure is a. a squared relationship. b. exponential. c. indirectly proportional. d. directly proportional
d. directly proportional
The area of the focal spot that is projected out of the tube toward the object being radiographed is the a. x-ray tube long axis. b. line focus. c. actual focal spot. d. effective focal spot.
d. effective focal spot.
The output screen absorbs ____ and emits ____. a. electrons; x-ray photons b. light photons; electrons c. light photons; x-ray photons d. electrons; light photons
d. electrons; light photons
Which one of the following occurs when the part is improperly aligned? a. magnification b. elongation c. minification d. foreshortening
d. foreshortening
If kVp is doubled, the amount of x-ray photons created approximately increases a. eightfold. b. twofold. c. threefold. d. fourfold.
d. fourfold.
The greater the voltage supplied to the electrostatic lenses, the ____ the acceleration and the ____ the focal point to the input screen. a. lesser; smaller b. greater; larger c. greater; farther d. greater; closer
d. greater; closer
Almost all of the kinetic energy of the incident electrons is converted to a. a bremsstrahlung photon. b. a characteristic x-ray photon. c. light. d. heat
d. heat.
Neon lights illustrate the fact that electrons will flow a. in a solid conductor. b. in an ionic solution. c. in a vacuum. d. in a gaseous environment.
d. in a gaseous environment.
If a DC circuit is a. in series, the currents are different for each component (e.g., resistors). b. in series, the voltages are the same for each component. c. in parallel, the currents are equal for all paths of the circuit. d. in parallel, the voltages are equal for all paths of the circuit.
d. in parallel, the voltages are equal for all paths of the circuit.
As the electron shells move farther from the nucleus, total electron energies ____ and binding energies____. a. decrease; increase b. increase; increase c. decrease; decrease d. increase; decrease
d. increase; decrease
As size distortion decreases, the resolution of recorded detail a. is not affected. b. decreases. c. is lost. d. increases.
d. increases
As the actual focal spot size increases, the effective focal spot size a. cannot be determined. b. decreases. c. remains the same. d. increases.
d. increases.
As the angle of the anode increases and the incident electron beam size remains the same, the effective focal spot size a. decreases. b. cannot be determined. c. remains the same. d. increases.
d. increases.
The relationship between the intensity of radiation and distance is the a. reciprocity law. b. 15 percent rule. c. direct square law. d. inverse square law.
d. inverse square law.
If a conductor is positively charged, it a. has more neutrons than electrons. b. is deficient in protons. c. has too many electrons. d. is deficient in electrons.
d. is deficient in electrons.
If a conductor is positively charged, it a. has too many electrons. b. has more neutrons than electrons. c. is deficient in protons. d. is deficient in electrons.
d. is deficient in electrons.
X-ray beam penetrability is primarily controlled by a. filtration. b. focal spot size and dimension. c. mAs. d. kVp.
d. kVp.
Bremsstrahlung interactions may occur only when the incident electron interacts with a. the nuclear force within the nucleus. b. an outer-shell electron. c. an inner-shell electron. d. the force field around the nucleus.
d. the force field around the nucleus.
The electrical device used to adjust the mA selection is a/an a. stator. b. autotransformer. c. diode. d. variable resistor.
d. variable resistor.
The unit of electrical power is a. ampere. b. joule. c. volt. d. watt.
d. watt.