Exams Flashcards
What is the purpose of the collimator shutters?
Absorb unneeded X-rays
Which of the following is responsible for changing AC current to DC current ?
Rectifier
What part limits the size of the useful x ray beam ?
The collimator
Which of the following types of anodes should you use ?
Rotating
How many rads are in a grey?
100
Who is credited with the discovery of an X-ray?
WC roentgen
From what does an electron cloud form?
The filament
In what country was x ray discovered?
Germany
What are examples of electromagnetic ionizing radiation ?
Gamma radiation and x ray
What is the last thing you should do before pressing exp.. button?
Activate the rotor
Where is oil normally found in the tube complex?
Between the tube and the tube housing
What makes up the majority of the x ray beam (85%) ?
Bremsstrahlung radiation
What is the international unit designation for the rad?
Gray
What material is used for the Construction of most compensating filters ?
Aluminum
Federal regulation requires how much filtration for an x ray machine that operates 70-100Kv
2.5
Which type of X-ray is associated with biological effects?
Ionizing
If you wanted to increase the number of photons reaching your film what should you do?
Increase the mas
What would have the least fluctuation in the kV level ?
High frequency
In checking you collimator, what percentage is the limit for inaccuracy?
2%
The MA setting determines what?
The current going through the filament
A tube warm up should be performed by using how many exposures ?
2
The initials FFD TFD SID refer to what?
The distance between the source of the X-ray and the film
Which type of dose is attributed to harmful effects from low levels of radiation ?
Genetic
What increases patient exposure to radiation?
Split screens
The large or small focal spot is usually set simultaneously with what?
The milliamperes
What is the beneficial effect of radiation called?
Radiation hormesis
If you had film that was too dark what would you do to solve the problem ?
Decrease the mas.
What is the function of the anode ?
To stop the electrons
Which part of the x ray is the target located in?
Anode
Radon comes to use in what form?
Alpha particles
The number of electrons is controlled by what?
Low voltage circuit
When is a fetus most sensitive to radiation?
1st trimester
Are X-rays stored in matter?
No
About how much recursion of gonad exposure occurs with a P-A film compared to an A-P lumbar film ?
95%
What is the best way to identify a patients film?
A flash on label before processing
What is the most commonly used dosimeter?
A film badge
The filament is surrounded by what structure?
The focusing cup
The useful beam exits which part of the tube?
Window
What propels the electrons in an x ray ?
The kV
What produces thermionic emissions ?
The low voltage circuit
Before moving the tube stand on the track what must be accomplished ?
The lock must be released
Which how the following contributes the most radiation to a humans annual exposure ?
Radon gas, sun and stars, diagnostic x rays, consumer products. Nuclear power plants.
Radon gas
What part of the tube complex allows one to move the tube stand?
The tube track
What is responsible for the anode heel effect?
The bevel of the anode
How would you figure heat units ?
MA x time x kVp
Which of the following is not required to appear on the legal id marker?
The patients age and or birth date
What governs the speed of electrons ?
The kV
What is the half value layer used for?
For filtration recommendation
The main purpose of oil in the tube complex is for what?
Cooling the tube
If a photon sailed through space at a high rate of speed which has went into and out of a patient. What would ne the next thing you encounter ?
A grid
What does the 10 day rule concern?
Patients during a ten day period from the onset of menses
Which part of the tube complex will you have to unlock and move to set the tube distance to the upright later lumbar film ?
The tube stand
The boiling off of electrons is known as what?
Thermionic emission
What is most helpful in producing a good quality A-P full spine X-ray?
Having the anode towards the cervical
What is recommend for a full spine film?
Compensating filtration
Which effect would a smaller anode angle have compared to a larger angle?
It would create a clearer image
Is it true that some materials fluoresce when exposed to x ray?
Yes
At a set FFD and film size the less collimating used the______the film will be?
Cleaner
Positive beam limitation systems (PBL) would include what?
Semiautomatic collimation
What would happen in you lengthened the time of exposure?
Increase the number of photons hitting the patient
What year was x ray discovered ?
1895
What is used to tell us that the x ray beam is centered to the part being radiographed.
The light and mirror
Where is added filtration located?
On the port of the tube housing
What characteristic does a dual focus tube have that a single focus tube doesn’t?
Two filaments
When taking a A-P full spine film of a young female what structure should you be most concerned with reducing exposure to prevent the unlikely possibility of cancer?
Breast
