RAD 121 FINAL EXAM QUESTIONS AND
ANSWERS (ALREADY GRADED A+)
tungsten is chosen as the material for the filament and anode target due to its? -
ANSWER-high atomic number and melting point
which of the following is created when a portion of an x-ray photon's is absorbed, which
is also the primary source of occupational exposure - ANSWER-scatter radiation
the structure in the x-ray tube which is constructed of molybdenum, is negatively
charged, and serves to keep electrons in the electron cloud closely placed is the -
ANSWER-focusing cup
the collimator portion of the x-ray machine serves to restrict the beam by - ANSWER-
using lead shutters
which two factors, controlled by the radiographer on the control console, are the major
controlling factors primarily responsible for the quantity of x-ray photons in the beam? -
ANSWER-time and mA
which of the following statement is true concerning the rotating anode - ANSWER-it
rotates at speeds between 3400 and 10000 revolutions per minute
the filament serves an important function in the x-ray tube by - ANSWER-emitting
electrons when heated (thermionic emission)
the target of the x-ray tube is angled at ___ degrees from vertical to prevent excessive
absorption of x-rays have just created, and to allow then to exit the window of the tube
housing - ANSWER-5 to 20
which of the following selections must be multiplied together to solve for mAs? -
ANSWER-mA and time
which of the following selections changes the potential difference across the tube at the
time of the exposure, controlling the speed of the electrons, and detirmining the
penetrating ability of the x-ray beam - ANSWER-kVp
the actual focal spot size (on the focal tract) used during an x-ray exposure is detirmed
by - ANSWER-use a small or large filament
the part of the x-ray tube which is essentail in etablishing a vaccum needed for x-ray
production, and is contructed of glass (or metal) is the - ANSWER-envelope
,insulating oil is present in most tube housings to - ANSWER-dissipate heat
the portion of the x-ray tube constructed of lead (plus other metals) that prevents
radiation leakage and electrical shoch to the patient and the radiographer and
radiographer is the ______ - ANSWER-protective housing
the negatibe side of the x-ray tube which supplies free electrons if the ____ - ANSWER-
cathode
the setting on the control console which controls the difference in positibe and negative
terminals of the x-ray tube, and therefor detirmines how quickly and forcefully the
elctrons will move across the tube is - ANSWER-kVp
copper is one of the materials used in construction of the ___. this device has the ability
to quickly dissipate heat away from the area - ANSWER-rotating anode
in order to control the amount of current flowing through the filament circuit and the
resulting number of elections created for x-ray production, the technologist (control
panel) - ANSWER-mA
500 mA x ____= 100 mAs - ANSWER-0.2
300 mA x .08 sec = ______ mAs - ANSWER-24
if a satisfactory exposure is obtained with 12 mAs at 72" SID, what mAs will be required
to maintain the same exposure at 36" SID - ANSWER-3
if a satisfactory exposure is obtained with 80 mAs at 40" SID, what mAs will be required
to maintain the same exposure at 80" - ANSWER-320
___mA X 3/4 sec = 300 mAs - ANSWER-400
what technique would you need ti use in order too preform a portable of a femur in
traction with a 50 cm SID, if a given technique of 70 kVp at 8 mAs with 100 cm SID is
stated on the technique chart - ANSWER-70 kVp at 2 mAs
if a satisfactory exposure is obtained with 30 mAs at 40" SID what mAs will be required
to maintain the same exposre at 72" SID - ANSWER-97.2
Which of the following prime/principle factors affect(s) x-ray emission, and is/ are
controlled by the radiographer - ANSWER-SID, kVp, mAs
the visible difference between any two selected areas of brightness levels within the
displyed radiographic image is termed - ANSWER-contrast
, what is the relationship between the mAs and image receptor exposure - ANSWER-
direct
__ is the variation in size and shape of the image in comparison to the object it
represents - ANSWER-distortion
which of the following allows the radiographer to calculate the new exposure factors to
be used when the SID changes - ANSWER-exposure maintenace formula, direct
square law
an increase in mAs (with no other changes) results in - ANSWER-an increase in the
amount of x-ray photons
the source to image receptor distance (SID) affects the x-ray beam _____ and _____ -
ANSWER-intensity, divergence
which of the following statement is true due to the inverse square law - ANSWER-the
intensity of the radiation is inversely proportional to the square of the distance
_____ controls the penetrating ability, or the ability og an x-ray beam to pass through an
object - ANSWER-kVp
the major controlling factor which detirmined the quality of the x-ray beam is -
ANSWER-kVp
_____ determines the speed of the electrons in the electron stream that will strike the
anode target inside of the x-ray tube - ANSWER-kVp
the major controlling factor which determines the amount of the x-ray photons in the
useful beam and is directly related to the x-ray quantity is - ANSWER-mAs
_____ is the measurement of the x-rays beam's penetrating ability - ANSWER-quality
the amount of radiation striking the image receptor is termed - ANSWER-receptor
exposure
____ refers to the sharpness of the structural edges recorded in the image - ANSWER-
spatial resolution
200 mA x 1/2 sec - ANSWER-10 mAs
100 mA x 0.15 sec - ANSWER-15 mAs
400 mA x 10 ms - ANSWER-4 mAs
ANSWERS (ALREADY GRADED A+)
tungsten is chosen as the material for the filament and anode target due to its? -
ANSWER-high atomic number and melting point
which of the following is created when a portion of an x-ray photon's is absorbed, which
is also the primary source of occupational exposure - ANSWER-scatter radiation
the structure in the x-ray tube which is constructed of molybdenum, is negatively
charged, and serves to keep electrons in the electron cloud closely placed is the -
ANSWER-focusing cup
the collimator portion of the x-ray machine serves to restrict the beam by - ANSWER-
using lead shutters
which two factors, controlled by the radiographer on the control console, are the major
controlling factors primarily responsible for the quantity of x-ray photons in the beam? -
ANSWER-time and mA
which of the following statement is true concerning the rotating anode - ANSWER-it
rotates at speeds between 3400 and 10000 revolutions per minute
the filament serves an important function in the x-ray tube by - ANSWER-emitting
electrons when heated (thermionic emission)
the target of the x-ray tube is angled at ___ degrees from vertical to prevent excessive
absorption of x-rays have just created, and to allow then to exit the window of the tube
housing - ANSWER-5 to 20
which of the following selections must be multiplied together to solve for mAs? -
ANSWER-mA and time
which of the following selections changes the potential difference across the tube at the
time of the exposure, controlling the speed of the electrons, and detirmining the
penetrating ability of the x-ray beam - ANSWER-kVp
the actual focal spot size (on the focal tract) used during an x-ray exposure is detirmed
by - ANSWER-use a small or large filament
the part of the x-ray tube which is essentail in etablishing a vaccum needed for x-ray
production, and is contructed of glass (or metal) is the - ANSWER-envelope
,insulating oil is present in most tube housings to - ANSWER-dissipate heat
the portion of the x-ray tube constructed of lead (plus other metals) that prevents
radiation leakage and electrical shoch to the patient and the radiographer and
radiographer is the ______ - ANSWER-protective housing
the negatibe side of the x-ray tube which supplies free electrons if the ____ - ANSWER-
cathode
the setting on the control console which controls the difference in positibe and negative
terminals of the x-ray tube, and therefor detirmines how quickly and forcefully the
elctrons will move across the tube is - ANSWER-kVp
copper is one of the materials used in construction of the ___. this device has the ability
to quickly dissipate heat away from the area - ANSWER-rotating anode
in order to control the amount of current flowing through the filament circuit and the
resulting number of elections created for x-ray production, the technologist (control
panel) - ANSWER-mA
500 mA x ____= 100 mAs - ANSWER-0.2
300 mA x .08 sec = ______ mAs - ANSWER-24
if a satisfactory exposure is obtained with 12 mAs at 72" SID, what mAs will be required
to maintain the same exposure at 36" SID - ANSWER-3
if a satisfactory exposure is obtained with 80 mAs at 40" SID, what mAs will be required
to maintain the same exposure at 80" - ANSWER-320
___mA X 3/4 sec = 300 mAs - ANSWER-400
what technique would you need ti use in order too preform a portable of a femur in
traction with a 50 cm SID, if a given technique of 70 kVp at 8 mAs with 100 cm SID is
stated on the technique chart - ANSWER-70 kVp at 2 mAs
if a satisfactory exposure is obtained with 30 mAs at 40" SID what mAs will be required
to maintain the same exposre at 72" SID - ANSWER-97.2
Which of the following prime/principle factors affect(s) x-ray emission, and is/ are
controlled by the radiographer - ANSWER-SID, kVp, mAs
the visible difference between any two selected areas of brightness levels within the
displyed radiographic image is termed - ANSWER-contrast
, what is the relationship between the mAs and image receptor exposure - ANSWER-
direct
__ is the variation in size and shape of the image in comparison to the object it
represents - ANSWER-distortion
which of the following allows the radiographer to calculate the new exposure factors to
be used when the SID changes - ANSWER-exposure maintenace formula, direct
square law
an increase in mAs (with no other changes) results in - ANSWER-an increase in the
amount of x-ray photons
the source to image receptor distance (SID) affects the x-ray beam _____ and _____ -
ANSWER-intensity, divergence
which of the following statement is true due to the inverse square law - ANSWER-the
intensity of the radiation is inversely proportional to the square of the distance
_____ controls the penetrating ability, or the ability og an x-ray beam to pass through an
object - ANSWER-kVp
the major controlling factor which detirmined the quality of the x-ray beam is -
ANSWER-kVp
_____ determines the speed of the electrons in the electron stream that will strike the
anode target inside of the x-ray tube - ANSWER-kVp
the major controlling factor which determines the amount of the x-ray photons in the
useful beam and is directly related to the x-ray quantity is - ANSWER-mAs
_____ is the measurement of the x-rays beam's penetrating ability - ANSWER-quality
the amount of radiation striking the image receptor is termed - ANSWER-receptor
exposure
____ refers to the sharpness of the structural edges recorded in the image - ANSWER-
spatial resolution
200 mA x 1/2 sec - ANSWER-10 mAs
100 mA x 0.15 sec - ANSWER-15 mAs
400 mA x 10 ms - ANSWER-4 mAs
