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When an electron interacts with a tungsten anode which of these things can happen?
Brem's Radiation, K - Shell Radiation, Heat Production, Characteristic Radiation
During X-ray photon production approximately 90% of the photons produced are
Bremsstrahlung X-Rays
To maintain a constant optical density there must be a reduction of one half the mAs paired with an increase of the kVp.  What should the increase of the percetnage for kVp be?
Increase the kV by 15%
how fast do the electrons travel from cathode to anode?
1/2 the speed of light
Modified Scatter refers to which of the following interactions?
Compton Effect
The efficiency of most x-ray machine in production is about?
1% or less
What radiation is called Breaking Radiation?
Bremsstrahlung Radiation
Which of the following interactions does not involve Ionization?
Classical or Brem's Radiation
As the atomic number increases, the number of brem's and the strength of Brem's______increase or decrease?
INCREASES
In a tungsten target x-ray tube which of the following shells would produced the most diagnostically useful Characteristic radiation?
K Shell
The kV needed to produce Characteristic X-rays would be?
69kV or higher
True or False: In terms of Characteristic Radiation, are x-ray photons produced when an outer shell e- fills the hole of the ejected k shell e-?
True
As Filtration increases the strength of Brem's Radiation?  inc or dec
Increase
True of False: As the atomic number increases the number of characteristic radiation
True
As the mA increases...
the number of Brem's radiation increases and Characteristic radiation stays the same.
As filtration increases...
The overall energy of Brem's increases, but the number of Brem's decreaases and Characteristic radiation stays the same.
Quantity is measured in
R and mR
As mAs increases quantity:
Increase
As Distance increases Quantity...
Decreases
As quantity decreases, kV
decreases
As Quantity decreases, filtration
increases
A 15% increase in kV is the same as:
Doubling the mAs, Doubling the density.
A diagnostic radiograph of a skull requires 300 mA, 0.1 s and 70 k.  The radiologist determines that the contrast is too low and wants a more grey film.  How could you change the technique to make a higher contrast image? (hint increase the KV)
80 kV 15 mAs
True or False.  If the radiograph is overexposed or underexposed we dont follow the 15% rule to maintain density?
True
The electrons that travel from cathode to anode are called
Projectile Electrons
As the HVL increase quality:
Increases
As penetration increases quality
INCREASES
What type of filtration has a 2.0 Al equivalent
Added Filtration
What devices is used to measure ionization in the air?
Ionization Chamber, Geiger-Muller, Victoreen R Meter, Cutie Pie
X-Rays that are in the range of 10-15kV and are used in treating superficial structures are?
Grenz Rays
What type of x-ray interaction would occur at energies below 10 kV?
Classical
If the kV selected was 60, at what kV would be the average brem's radiation? (HINT 1/3rd Brem's Rad)
20 kV
What type of scatter radiation occurs when an x-ray interacts with an outer-shell electron at moderate energy and ionization occurs?
Compton Scatter
You produced an overexposed radiographic of the abdominal cavity using 400 mA .1s and 90 kV. The radiologist determines that the film is too dark.  How could you change the technique to produce a clearer image? (HINT decrease the kV)
77 kV @ 40 mAs
Which x-ray interaction occurs below 10 kV , no ionization occurs, and the x-ray photon, looses no energy?
Classical
What is minimum energy for pair production to occur?
1.02 MeV
The thin end of a wedge filter should be placed at which end of the foot for a properly exposed radiograph?
Heel
What are the two energy levels of the 2 e- that were annihilated?
.51 MeV
What is the energy level needed for photodisintegration to occur?
10 mEv or higher
Which x-ray interaction occurs when a high energy e- strikes a nucleus and ejects a nuclear fragment?
photodisintergration
Which x-ray interaction occurs when the incident photon is totally absorbed and ionization occurs when the inner shell e- is ejected?
photoelectric
What is the total filtration for most hospital x-ray machines?
2.5 mm Al
At what level does photodisintegration occur?
10 MeV
What happens when filtration is added to an x-ray tube?
Radiation quality increases
A diagnostic technique for a hand x-ray at 5 mAs.  However, the contrast is too low so the kV needs to be reduced.  What is the new technique that will produce the same quality radiograph with higher contrast?
60 kV and 10 mAs  reduce kV and double mAs
A 15% decrease in kV is the same as 
Halving the mAs
The energy of the characteristic radiation is the difference in
BINDING ENERGIES
The X-ray interaction with matter that is responsible for the majority of scattered radiation reaching the IR and contributes most to occupational exposure is?
COMPTON SCATTER
The photoelectric effect is an interaction between an x-ray phton and ?
a inner-shell electron
Filters used in radiographic x-ray tybes are generally composed of?
Aluminum  Al
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