Review
Thermionic emission at the filament determines the _____ across the xray tube during an exposure.
milliamperage
a neutral atom has the same number of _________ and electrons.
protons
the filament in an xray tube is about ________ cm in length
1 to 2
the step up transformer increases voltage _______ times
500 to 1000
tube failure can occur from __________.
long exposure times
The negative side of the xray tube holds the ____
filament
the biggest source of man-made ionizing radiation exposure to the public is ___________
diagnostic xrays
which has the greatest mass density?
bone
The atomic number of an element is symbolized by the letter ______.
Z
number of electrons boiled off the filament
If the SID is reduced by half, how if the xray intensity at the image affected?
It is increased by 4
Variation in power distribution to the xray machine are corrected by the __________
line voltage compensator
lowering kVp ______ patient dose and _________ image contrast.
increases : increases
The ________ circuit provides electrons for the xray tube current.
filament
the diagnostic range of xray energy is _________.
30 to 150 kVp
If a radiographer changes the technique from 70 kVp @ 200 mAs to 80 kVp @ 200 mAs, the intensity will ____.
double
advantages of a rotating anode includes all of the following except
used in both general purpose xray tubes and dental xray imaging systems
when only the intensity needs to be changes, only the _______ should be adjusted.
mAs
The most commonly used beam restricting device is the __________.
light localizing variable aperature collimator
Attenuation is reduction in the intensity of the xray beam as the result of _________.
photoelectric absorption and compton scattering.
cathode to anode.
the production of heat at the anode is directly proportional to _____________.
tube current
Characteristic K-shell xrays have an effective energy of ____ keV
69
beam penetrability is increased if __________ is increased
kVp
As an xray tube ages, the inside can become coated with tungsten, which can cause _______ in the tube.
arcing