FQ1 Flashcards
The purpose of a rectifier is to:
convert AC to DC current
Which of these rectifiers is consistent with the ALARA concept?
high frequency
what is ionization?
the total removal of an ELECTRON from its atomic shell level
The radiographic density is excellent using 30 mAs at 73 kVp at 40’’ SID. What change in exposure factors is necessary when changing to 80’’ SID?
120 mAs, 73 kVp
The quality factor of x-ray is _______.
1
REM=RAD x ______.
QF
5 REM = __________ mrem.
5,000
Which x-ray interaction with matter is the most likely to occur in high atomic number matter?
photoelectric absorption
Which x-ray interaction with matter has a probability of occurrence if the x-ray is in the 10-60 keV range?
photoelectric absorption
Which x-ray interaction with matter has a probability of occurring when the x-ray energy is in the 60-125 keV range?
compton scatter
The original x-ray no longer exists when this x-ray interaction with matter occurs.
photoelectric absorption
“Fog” on the image is the result of this x-ray interaction with matter.
compton scatter
The exposure factors are correct when performing a 14’’ x 17” AP lumbar spine exam using 80 mAs at 73 kVp. If the x-ray beam is collimated to a 6” x 17” area the exposure factors should be:
120 mAs, 73 kVp
The optimum kVp range for images of the spine is in this range.
70-90 keV
The optimum kVp range for non Bucky images of the extremities is in this range
50-60 keV
The purpose of a “Bucky” grid is to:
reduce “fog” from compton scatter
Which of these grids would require the most exposure to the patient?
16:1
The x-ray beam may be angled in this direction when using a linear grid.
in the direction of the strips
Which of these grids requires that the SID be within a very specific range?
focused
Intensifying screens are used with film to:
reduce radiation exposure
Which of these imaging systems would you choose to image extremities?
100 speed
Which of these imaging systems will result in the most quantum mottle in the image?
1200 speed
A GBX safelight filter is:
red
An AP lumbar spine film is exposed properly using 30 mAs, 73 kVp with a 200 speed film screen combination. What exposure factors should be used if the film screen system is changed to a 600 speed system?
10 mAs, 73 kVp
Silver is recovered from this processing chemistry.
fixer
****** processing system should be *****, cleaned, replenished and servived every _____ weeks.
4
On the radiograph, radiographic density appears ________.
black
On a radiograph, high atomic number, dense anatomy appears
white
The total number of x-rays in the beam is controlled by selecting the _________.
mAs
Which of these sets of exposure factors will produce an image with the shortest scale of contrast?
62 kVp, 60 mAs
The intensity of radiation standing 3 feet from the tube housing is 100 mR/hr. What is the intensity of radiation if you step back to 6 feet?
25 mR/hr
The technique chart requires 30 mAs, 73 kVp for a 20 cm AP thoracic spine exam. What should the exposure factors be if there is a 6” space between the patient’s thoracic spine and the image receptor?
45 mAs, 73 kVp
The technique chart says that a 14 x 17” AP thoracic spine image will require 30 mAs, 73 kVp. If a decision is made to collimate down to a 4 x 4” spot view of T-6 what will the exposure factors need to be?
45 mAs, 73 kVp
As mA increases, the cathode filament:
gets hotter
Which of these will produce the most skin dose?
short SID
An image is so underexposed that it needs to be retaken when the exposure factors were 30 mAs, 73 kVp. The new exposure factors should be:
60 mAs, 73 kVp
Linearity is the ability to:
manipulate the mA x seconds for the same mAs and get the same result
According to Dr. Bushong, therapeutic absorption should not be considered with exposures below ____ RAD to the abdominal area of a pregnant woman.
10
The ten day rule suggests that x-rays of a female with reproductive ability should only be performed:
in the 10 days following the onset of menstruation
To be provided with dosimetry, education and possible reassignment of duty, a pregnant employee must:
declare the pregnancy in writing to the employer