| Common cause of tube failure. | TUNGSTEN VAPORIZATION WITH DEPOSITION ON THE INSIDE OF THE GLASS |
| Is the quantity of matter as described by its energy equivalence. | MASS |
| The ability to do work. | ENERGY |
| Is the transfer of energy. | RADIATION |
| Is the removal of an electron from an atom. | IONIZATION |
| To provide an x-ray beam that is satisfactory for imaging, you must supply the x-ray tube with a _____ and _______. | HIGH VOLTAGE AND AN ELECTRIC CURRENT |
| Emerged as a medical specialty
because of the Snook transformer and the Coolidge x-ray tube. | RADIOLOGY |
| ALARA stands for | AS LOW AS REASONABLY ACHIEVABLE |
| Is based on the vibration of atoms of cesium. | SECOND (s) |
| The velocity of light is constant and is sybolized by _____. | c: c = 3 × 10^8 m/s. |
| Law: A body will remain at rest or will continue to move with constant velocity in a straight line unless acted on by an external force. | NEWTON'S FIRST LAW: INERTIA |
| The force (F) that acts on an object is equal to the mass (m) of the object multiplied by the acceleration (a) produced. | NEWTON'S SECOND LAW: FORCE |
| Is the product of mass and velocity | MOMENTUM |
| Is the quotient of work by time. | POWER |
| Is the product (multiplication of) of force and distance | WORK |
| Is the ability to do work. | ENERGY |
| Is the kinetic energy of the random motion of molecules. | HEAT |
| Is the transfer of heat through a material or by touching. | CONDUCTION |
| Is the mechanical transfer of "hot" molecules in in a gas or liquid from one place to another. | CONVECTION |
| Is the transfer of heat by the emission of infrared radiaiton. | THERMAL RADIATION |
| Is the unit of radiation exposure or intensity. | Air kerma (Gya) |
| Is the unit of Radiation Absorbed Dose. | Gray (Gyt) |
| Is the unit of occupational radiation exposure and effective dose. | Sievert (Sv) |
| Is the unit of radioactivity. | Becquerel (Bq) |
| The smallest particle that has all the properties of an elemnt. | ATOM |
| The fundamental particles of an atom are: | ELECTRON, PROTON, AND NEUTRON |
| Is essentially empty space. | ATOM |
| In their normal state, atoms are electrically ____; the elctric charge on the atom is _____. | NEUTRAL, ZERO |
| The removal or addition of an orbital electron from an atom. | IONIZATION |
| No outer shell can contain more than how many electrons? | EIGHT |
| What is the force that keeps the electron in orbit? | CENTRIPETAL FORCE |
| EQUAL or NOT EQUAL: The atomic mass number and the precise mass of an atom. | NOT EQUAL |
| Have the same atomic number but different atomic mass number. | ISOTOPES |
| Atomic nuclei that have the same atomic mass number but different atomic numbers. | ISOBAR |
| Have the same number of neutrons but different numbers of protons. | ISOTONE |
| Have the same atomic number and the same atomic mass number. | ISOMER |
| Atoms of various elements may combine to form structures are called ____. | MOLECULES |
| The smallest particle of an element is ______.
The smallest particle of a compound is ______. | AN ATOM, A MOLECULE |
| The emission of particles and energy in order to become stable. | RADIOACTIVITY |
| This results in emission of alpha particles, beta particles, and usually gamma rays. | RADIOACTIVE DECAY |
| Is the time required for a quantity of radioactivity to be reduced to one-half its original value. | HALF-LIFE OF A RADIOISOTOPE |
| 3.3 half lives = _____ life | 1 TENTH LIFE |
| Is a helium nucleus that contains two protons and two neutrons. | ALPHA PARTICLE |
| Is an electron emitted from the nucleus of a radioactive atom. | BETA PARTICE |
| Is a quantum of electromagnetic energy. | X-RAY PHOTON |
| The velocity of all electromagnetic radiation is ______. | 3 x 10^8 m/s |
| Is one-half the range from crest to valley over which the sine waves varies. | AMPLITUDE |
| Is the number of wavelengths that pass a point of observation per second. | FREQUENCY |
| Is the distance from one crest to another, from one valley to another, or from any point on the sine wave to the next corresponding point. | WAVELENGTH |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
At a given velocity, wavelength and frequency are ______. | INVERSELY PROPORTIONAL |
| Includes the entire range of electromagnetic energy. | ELECTROMAGNETIC SPECTRUM |
| TRUE or FALSE: Diagnostic ultrasound is not a part of the electromagnetic spectrum. | TRUE |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
The energy of a photon is _____ proportional to its frequency. | DIRECTLY PROPORTIONAL |
| The only difference between x-rays and gamma rays. | ORIGIN |
| ______ is identified by wavelength,
______ is identified by frequency, and
______ are identified by energy. | VISIBLE LIGHT, RADIOFREQUENCY, X-RAYS |
| Interact with matter most easily when the matter is approx. the same size as the photon wavelength. | PHOTONS |
| They behave as though they are particles. | X-RAYS |
| Behaves like a wave. | VISIBLE LIGHT |
| Is the reduction in intensity that results from scattering and absorption. | ELECTROMAGNETIC ENERGY ATTENUATION |
| DIRECTLY RELATED or INVERSELY RELATED:
Electromagnetic energy (radiation) intensity is _____ related to the square of the distance from the source. | INVERSELY RELATED |
| Can be applied to distances greater than seven times the longest dimension of the source. | INVERSE SQUARE LAW |
| Is a discrete bundle of energy. | X-RAY PHOTON |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
The energy of a photon is ____ proportional to its frequency. | DIRECTLY PROPORTIONAL |
| Is the study of stationary electric charges. | ELECTROSTATIC |
| Has mass and energy equivalence. Also may have electric charge. | MATTER |
| Can be created by contact, friction, or induction. | ELECTRIFICATION |
| Unlike charges _____; like charges _____. | ATTRACT, REPEL |
| LAW: The electrostatic force is directly proportional to the product of the electrostatic charges and inversely proportional to the square of the distance between them. | COULOMB'S LAW |
| The distribution of this is uniform throughout or on the surface. | ELECTRIC CHARGE |
| A conductor of this is concentrated along the sharpest curvature of the surface. | ELECTRIC CHARGE |
| The unit of electric potential. | Volt (V) |
| The study of electric charges in motion. | ELECTRODYNAMICS |
| Is any substance through which electrons flow easily. | CONDUCTOR |
| Is any material that does not allow electron flow. | INSULATOR |
| Is a material that under some conditions behaves as an insulator and in other conditions behaves as a conductor. | SEMICONDUCTOR |
| INCREASING or DECREASING:
_______ electric resistance results in a reduced electric current. | INCREASING |
| LAW: The voltage across the total circuit or any portion of the circuit is equal to the current times the resistance. | OHM's LAW |
| In a series circuit, all circuit elements are connected in a line along the same _____. | CONDUCTOR |
| Contains elements that are connected at their ends rather than lying in a line along a conductor. | PARALLEL CIRCUIT |
| Electrons that flow in only one directions constitute ___; electrons that flow alternately in opposite directions constitute ___. | DC;AC |
| ____ watt is equal to 1 A of current flowing through an electric potential of 1 V.
Power (W) = voltage (V) x current (A) | ONE |
| Any charged particle in motion creates a ______. | MAGNETIC FIELD |
| OPEN or CLOSED: The lines of a magnetic field are always ____ loops. | CLOSED |
| Is the ability of a material to attract the lines of magnetic field intensity. | MAGNETIC PERMEABILITY |
| Are classified according to the origin of the magnetic property. | MAGNETS |
| All matter can be classified according to the manner in which it interacts with a/an _______. | EXTERNAL MAGNETIC FIELD |
| The degree to which a material can. be magnetized is its _____. | MAGNETIC SUSCEPTIBILITY |
| Can be made into magnets by induction. | FERROMANETIC OBJECTS |
| Is proportional to the product of the magnetic pole strengths divided by the square of the distance between them. | MAGNETIC FORCE |
| The SI unit of magnet field strength is the _____.
An older unit is the ____. | TESLA (T), GAUSS (G) |
| 1 tesla (T) = ____ gauss (G) | 10,000 |
| Is measured in units of joule per coulumb, or volt. | ELECTRIC POTENTIAL |
| Any charge in motion induces a _____. | MAGNETIC FIELD |
| A coil of wire is called _____. | SOLENOID |
| Is a current-carrying coil of wire wrapped around an iron core, which intensifies the induced magnetic field. | ELECTROMAGNET |
| An electric current is induced in a circuit if some part of the circuit is in a changing magnetic field. | ELECTROMAGNETIC INDUCTION |
| Varrying magnetic field intensity induces a/an _____. | ELECTRIC CURRENT |
| A/An _______ powers the rotating anode of an x-ray tube. | INDUCTION MOTOR |
| This changes the intensity of alternating voltage and current. | TRANSFORMER |
| Has one winding and varies both voltage and current. | AUTOTRANSFORMER |
| Has a single winding and is designed to supply a precise voltage to the filament circuit and to the high-voltage circuit of the x-ray imagine system. | AUTOTRANSFORMER |
| Determines the quality of the x-ray beam. | kVp |
| Is the release of electrons from a heated filament. | THERMIONIC EMISSION |
| The product of x-ray tube current (mA) and exposure time(s) is mAs, which is also ____. | ELECTROSTATIC CHARGE (C) |
| Most exposure timers are electronic and are controlled by a _____. | MICROPROCESSOR |
| Are used on falling-load and capacitor discharge imaging systems. | mAs timers |
| Three primary parts of the high-voltage generator: | HIGH-VOLTAGE. TRANSFORMER, FILAMENT TRANSFORMER, and RECTIFIERS |
| Radiographers outside the United States and Japan may use a frequency of ______. | 50 Hz |
| Is the process of converting AC to DC | RECTIFICATION |
| Is required to ensure that electrons flow from x-ray tube cathode to anode only. | VOLTAGE RECTIFICATION |
| Is used when medical imaging systems are described | ELECTRON FLOW |
| With this, the voltage applied across the x-ray tube is nearly constant, never dropping to zero during exposure. | THREE-PHASE POWER |
| Is used in almost all stationary x-ray imaging systems. | FULL-WAVE RECTIFICATION or HIGH-FREQUENCY VOLTAGE GENERATION |
| During capacitor discharge, the voltage falls approximately ____ kV/mAs. | 1 |
| GREATER or LESSER:
Less voltage ripples results in _____ radiation quantity and quality. | GREATER |
| = maximum x-ray tube current (mA) at 100 kVp and 100 ms | High-voltage generator power (kW) |
| Guards against excessive radiation exposure and electric shock. | PROTECTIVE HOUSING |
| Are designed with a glass or a metal enclosure. | X-RAY TUBE |
| Two primary parts of the Cathode | FILAMENT AND FOCUSING CUP |
| Common cause of tube failure. | TUNGSTEN VAPORIZATION WITH DEPOSITION ON THE INSIDE OF THE GLASS ENCLOSURE |
| Is adjusted by controlling the filament current. | X-RAY TUBE CURRENT |
| At low kVp and high mA can be space charge limited. | THERMIOIC EMISSION |
| It conducts electricity and radiates heat and contains the target. | ANODE |
| YES or NO: Are higher tube currents and shorter exposure times possible with the rotating anode? | YES |
| Is powered by an electromagnetic induction motor | ROTATING ANODE |
| Is the actual x-ray source. | FOCAL SPOT |
| Results in an effective focal spot size much less than the actual focal spot size. | LINE-FOCUS PRINCIPLE |
| The smaller the anode angle, the ___ the heel effect. | LARGER |
| Results in smaller effective focal spot and less radiation intensity on the anode side of the x-ray beam. | HEEL EFFECT |
| Results in reduced x0ray tube life. | EXCESSIVE HEAT |
| Should never be applied to a cold anode. | MAXIMUM RADIOGRAPHIC TECHNIQUES |
| The most frequent cause of abrupt tube failure is electron arcing from the filament to the enclosure because of _____. | VAPORIZED TUNGSTEN |
| Is the energy of motion. | KINETIC ENERGY |
| Appoximately __% of the kinetic energy of projectile electrons is converted to heat. | 99 |
| Are emitted when an outer-shell electron fills an inner-shell void. | CHARACTERISTIC X-RAYS |
| The only characteristic x-rays of tungsten that are useful for imaging. | K-CHARACTERISTIC X-RAYS |
| This type of x-radiation is called _______ because it is characteristic of the target element. | CHARACTERISTIC |
| Are produced when a projectile electron is slowed by the nuclear field of a target atom nucleus. | BREMSSTRAHLUNG X-RAYS |
| In the diagnostic range, most x-rays are _____ x-rays. | BREMSSTRAHLUNG X-RAYS |
| A _______ spectrum contains only specific values. | DISCRETE |
| A _____ spectrum contains all possible values. | CONTINUOUS |
| Have precisely fixed (discrete) energies and form a discrete emission spectrum. | CHARACTERISTIC X-RAYS |
| Have a range of energies and form a continuous emission spectrum. | BREMSSTRAHLUNG X-RAYS |
| Is associated with the minimum x-ray wavelength (λmin). | MAXIMUM X-RAY ENERGY |
| A change in ________ results in a proportional change in the amplitude of the x-ray emission spectrum at all energies. | mA or mAs |
| A change in ____ affects both the amplitude and the position of the x-ray emission spectrum. | kVp |
| Does changing the kVp affect the position of the discrete x-ray emission spectrum? | NO, IT DOESN'T |
| In the diagnostic range, a ___% increase in kVp is equivalent to doubling the mAs. | 15 |
| The result of ______ is an increase in the average energy of the x-ray beam with an accompanying reduction in x-ray quantity. | ADDED FILTRATION |
| Increasing _______ enhances the efficiency of x-ray production and the energy of characteristic and bremsstrahlung x-rays. | TARGET ATOMIC NUMBER |
| Because of ________, operation with three-phase power or high frequency is equivalent to an approximate 12% increase in kVp, or almost doubling of mAs over single-phase power. | REDUCED RIPPLE |
| Is the number of x-rays in the useful beam. | X-RAY QUANTITY |
| X-ray quantity is proportional to _____. | mAs |
| X-ray quantity is proportional to the _____. | kVp^2 |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
X-ray quantity is ______ to the square of the distance from the source. | INEVRSELY PROPORTIONAL |
| When SID is increased, mAs must be _____ by SID^2 to maintain constant exposure to the image receptor. | INCREASED |
| Adding filtration to the useful x-ray beam _____ patient dose. | REDUCES |
| Is one description of the ability of an x-ray beam to pass through tissue. | PENETRABILITY |
| Is the reduction in x-ray intensity that results from absorption and scattering. | ATTENUATION |
| Is the thickness of absorbing material necessary to reduce the x-ray intensity to half of its original value. | HVL OF AN X-RAY BEAM |
| The best method for specifying x-ray quality. | HVL |
| X-ray beam quality can be identified by kVp or filtration, but ____ HVL is most appropriate. | HVL |
| INCREASES or DECRAESES:
Increasing filtration ______ the quality of an x-ray beam. | INCREASES |
| INCREASED or DECREASED:
Added filtration results in _____ HVL. | INCREASED |
| This type of interaction with matter is of little importance to diagnostic radiology. | COHERENT SCATTERING |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
The probability of Compton scattering is ________ proportional to x-ray energy (1/E) and independent of atomic number. | INVERSELY PROPORTIONAL |
| INCREASES or REDUCES:
Compton scattering _____ image contrast. | REDUCES |
| ____ is total x-ray absorption. | PHOTOELECTRIC EFFECT |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
The probability of the photoelectric effect is _____ proportional to the third power of the x-ray energy (1/E)^3 | INVERSELY PROPORTIPONAL |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
The probability of photoelectric effect is ____ proportional to the third power of the atomic number of the absorbing material. | DIRECTLY PROPORTIONAL |
| Does pair production occur during x-ray imaging? | NO |
| Does photodisintegration occur in diagnostic imaging? | NO |
| Occurs because of Compton scattering, photoelectric effect, and x-rays transmitted through the patient. | DIFFERENTIAL ABSOPTION |
| INCREASES or REDUCES: Differential absorption _____ as the kVp is reduced. | INCREASES |
| HIGH or LOW: To image small differences in soft tissue, one must use ____ kVp to get maximum differential absorption | LOW |
| PROPORTIONAL or INVERSELY PROPORTIONAL:
The interaction of x-rays with tissue is _____ to the mass density of the tissue regardless of the type of interaction. | PROPORTIONAL |
| The product of absorption and scattering. | ATTENUATION |
| Spatial resolution improves as screen blur _____, motion blur ____, and geometric blur ____, | DECREASES 3x |
| The random fluctuation in the OD of the image. | RADIOGRAPHIC NOISE |
| INCREASES or REDUCES:
The use of high-mAs, low-kVp and slower image _____ quantum mottle. | REDUCES |
| An increase in LRE of 0.3 results from _____ the radiation exposure. | DOUBLING |
| INCREASES or REDUCES: Higher fog density ________ the contrast of the radiographic images. | REDUCES |
| Base plus fog OD has a range of approximately _____. | 0.1 to 0.3 |
| States that the OD on a radiograph is proportional only to the total energy imparted to the radiographic film and independent of the time of exposure. | RECIPROCITY LAW |
| Film contrast is elated to the _______ portion of the characteristic curve. | SLOPE OF THE STRAIGHT-LINE |
| DIRECTLY PROPORTIONAL or INVERSELY PROPORTIONAL:
Latitude and contrast are _____ proportional. | INVERSELY |
| 3 Geometric factors | MAGNIFICATION, DISTORTION, and FOCAL-SPOT BLUR |
| Unequal magnification of different portions of the same object. | SHAPE DISTORTION |
| the location of something surrounded by other things | THICK, THIN |
| Occurs if the object plane and the image plane are not parallel. | DISTORTION |
| Occurs because the focal spot is not a point. | FOCAL-SPOT BLUR |
| The most important factor for determining spatial resolution | FOCAL-SPOT BLUR |
| Is small on the anode side and large on the cathode side of the image. | FOCAL-SPOT BLUR |
| The most important influence on subject contrast. | kVp |
| Usually the cause of motion blur. | PATIENT MOTION |
| Keep exposure time as ____ as possible. | SHORTÍ |
