Study sets, textbooks, questions
Upgrade to remove ads
Mosby Review Questions for X-ray Equipment Operation
Terms in this set (100)
In many cases, digital fluoroscopy eliminates which of the following?
Postprocedure "overhead" images
What is the smallest particle of an element that retains the characteristics of the element?
In digital fluoroscopy, the image must be turned into digital form by what device?
X-rays travel as bundles of energy called
What is atomic mass?
The number of protons plus the number of neutrons
What device may be used to ensure consistency of radiographic quality from one exposure to the next?
Automatic exposure control
When a predetermined level of ionization is reached in the ionization chamber, what does the machine do?
The exposure is terminated
What type of x-ray machine uses a continually decreasing mA for the shortest times possible?
Falling load generator
What type of current is required for proper operation of the x-ray tube?
The law stating that the outer shell of an atom can contain no more than eight electrons is called
Examples of particulate radiation are
Helium nuclei and beta particles
Electromagnetic radiation travels
In waves along a straight path
The latest digital fluoroscopic units use
Flat panel plates similar to DR
At what speed do x-rays travel?
The speed of light 186,000 miles per second
Waves of radiation are called
Wavelength is defined as the distance from
Peak to peak of the wave
Frequency is defined as
The number of waves passing a point per unit time
The speed of x-rays is based on
The fact that they are a form of electromagnetic radiation
Wavelength and frequency are
Inversely proportional to each other
The x-ray beam changes as it travels through the patient by a process called
The intensity of radiation is inversely proportional to the square of the distance between the source of radiation and the person receiving it. This describes the
Inverse square law
As radiation strikes matter
The energy is transferred to the atoms according to the law of conservation of energy
Choose all of the following statements that are accurate regarding electrostatic charges.
Electrostatics is the study of electric charges at rest.
Electrostatic charges concentrate on a conductor in the area of greatest curvature.
Choose all of the following that are accurate (choose 6):
A magnetic field always surrounds an electric charge in motion.
Current flows back and forth in AC.
Current flows in one direction in DC.
A conductor allows the flow of electrons.
The volt is the unit of potential difference.
The path of electrical current is called the circuit.
Electromagnetic induction is the process of causing an electrical current to flow in a conductor
when it is placed in the magnetic field of another conductor
The two types of electromagnetic induction are
Self-induction and mutual induction
Self-induction is used in the operation of what device?
The strength of the magnetic fields in a transformer is increased by
coiling the wires and letting their magnetic fields overlap
Electricity is supplied to the imaging department by a
The electricity provided to the radiology department is
60 Hz AC
The electricity provided to the radiology department operates at
120 pulses per second
Has almost no ripple
The primary advantage of three-phase power is that
Voltage never drops to zero
A variable transformer that is used to select kVp for the x-ray circuit is the
A transformer that has more turns in the secondary coil than in the primary coil is called a
What is the transformer used to boost voltage to kilovoltage levels called?
Voltage coming to the x-ray machine is kept constant through the use of a
Line voltage compensator
A step-down transformer
Steps down voltage
Where does thermionic emission occur?
Which of the following devices is prereading?
Which device reduces voltage and provides current to produce an electron cloud or space charge at the filament?
Which device is electronic, with a setting as low as 0.01?
What changes AC to DC?
Which of the following is surrounded by a negatively charged focusing cup?
Which of the following is composed of solid-state silicon based diodes?
What regulates the duration of x-ray production?
What is located in the x-ray circuit between the high-voltage transformer and the x-ray tube?
Which of the following measures tube current?
What device spins at 10,000-12,000 rpm?
What device uses maximum heat storage ability of the tube to deliver mAs?
Falling load generator
What is the source of bremsstrahlung and characteristic rays?
What device increases voltage approximately 500 times?
What is the most commonly used AEC?
What device always delivers the shortest exposure time possible?
Falling load generator
What device is turned by a rotor?
Which of the following is located between the patient and the image receptor?
The filament is kept warm by
A standby current from the time the x-ray machine is turned on
Activating the rotor
reduces tube life
When making an exposure, the radiographer should
Activate the rotor and exposure switch in one continuous motion
The process of thermionic emission causes
Electrons to boil off the filament
The force with which the electron stream passes from cathode to anode is a result of _____________ passing through the x-ray tube.
Heat is produced in the x-ray tube as
Electrons interact with the target material
Most of the energy conversion in the x-ray tube produces
X-rays are produced as incident electrons are slowed going past the nuclei of target atoms by a process called
X-rays are produced as incident electrons collide with inner shell electrons in target atoms by a process called
What percentage of energy in the x-ray tube is converted to x-rays?
Choose all that are properties of x-rays (choose 6):
Affect film emulsion
Scatter and produce secondary radiation
Invisible to the human eye
Travel in bundles of energy called photons
Can ionize matter and gases
Cause phosphors to fluoresce
The x-ray beam is
Heterogenous or polyenergetic - consisting of many different energies (wavelengths)
The x-ray emission spectrum consists of
Discrete spectrum (produced by characteristic rays) and continuous spectrum (produced by brems rays)
The primary purpose of filtration is
The amount of material needed to reduce the intensity of the beam by 1/10 is called
Which of the following statements regarding filtration is true?
Total filtration (not less than 2.5 mm aluminum equivalent) = inherent filtration (glass envelope, tube housing oil) + added filtration (aluminum)
Calculating heat units for three-phase, 12-pulse equipment requires the use of _________ as a constant
Calculating heat units for single-phase equipment requires the use of ________ as a constant
Calculating heat units for three-phase, 6-pulse equipment requires the use of _______ as a constant
When a quality control test is performed to ensure that the penetrating ability of the x-ray beam is accurate, the result must be within what amount of the control panel setting?
The primary type of grid used in digital imaging is
The portion of the image intensifier tube that converts electron energy to visible light is the
The portion of the image intensifier tube that converts visible light to electrons is the
The input phosphor of the image intensifier tube converts
X-rays and heat to visible light
Total brightness gain achieved using an image intensifer equals
Flux gain x minification gain
Single-phase, full-wave rectification produces
Pulsating direct current with 120 pulses per second and 100% ripple
Three-phase, 6 pulse full-wave rectification produces
Direct current with 13% ripple
Three-phase, 12 pulse full- wave rectification produces
Direct current with 4% ripple
The increase in average photon energy when using three-phase, 6-pulse equipment compared with single-phase equipment is
The increase in average photon energy when using three-phase, 12-pulse equipment compared with single-phase equipment is
Programs that deal with the safe and reliable operation of equipment and programs that address all aspects of the delivery of radiology services are called, respectively
Quality control and quality assurance
An image intensifier's conversion factor is expressed as the ratio of
The luminance of the output phosphor to the exposure rate at the input phosphor
The collimator must be accurate to a level of
± 2% SID
kVp must be accurate to within
10% of the control panel setting
Exposure linearity must be accurate to within
Eposure reproducibility must be accurate to within
Fluoroscopy exposure rate may not exceed
100 mGya per minute
The feauture that automatically adjusts kVp and mA during fluoroscopy is called
ABC (Automatic Brightness Control)
The test that measures the accuracy of adjacent mA stations is
The test that measures the accuracy of successive exposures is
The accuracy of the timer must be within
5% of the time chosen for exposures over 10 ms
Resolution of the television system may be measured using the following tool
Wire mesh test
AECS may be tested using
The number of mAs used for analog fluoroscopy is
3 to 5
Marks on the focal track of the anode resulting from bombardment of electrons are called
Effective quality control and quality assurance programs are required for accreditation by
The Joint Commision (TJC)
Sets found in the same folder
Mosby's Review: Chapter 4: Image Production (xray…
Comprehensive Review of Radiography: Safety
Mosby Chapter 5 - Procedures
'Physics' Chapter 1
Other sets by this creator
LANGE Practice Test 2 Questions
10: Criteria for Image Evaluation
9: Image Processing and Quality Assurance
8: Selection of Technical Factors
Other Quizlet sets
U.S History Topic 7
CHAPTER 1 🌵🌵
Econ 002- Ch. 1