Quiz 2 Flashcards
What are the radiation units for ABSORBED DOSE (Customary & SI)?
- Customary
- SI
- Rad
2. Gray (Gyt)
What are the radiation units for EXPOSURE (Customary and SI)?
- Customary
2a. SI
2b. SI
- Roentgen (R)
2a. Air Kerma (Gya)
2b. Coulombs per Kilogram (C/kg)
What are the radiation units for EQUIVALENT DOSE (Customary & SI)?
- Customary
- SI
- Rem
2. Seivert (Sv)
What are the radiation units for RADIOACTIVITY (Customary & SI)
- Customary
- SI
- Curie (Ci)
2. Becquerel (Bq)
When converting SI units and Customary units, ___ Customary units = ___ SI units. (Except for Coulombs***)
100 Customary= 1 SI
Exposure in air: 1 Roentgen is also equivalent to _____ x 10^-4 C/kg
2.58
What are the two internal components of the xray tube?
Anode
Cathode
What are the three external components of the xray tube?
Support Structure
Protective Housing
Glass Envelope or Metal Enclosure
The tube housing is required to reduce radiation to less than:
100mR/hr
Which design does the tube envelope resemble?
Coolidge
The Cathode is made up of ________ tungsten.
Thoriated
(Dual Focus Tubes/ Filaments)
Large filaments produce ____ - 1.2 mm focal spots.
0.4
(Dual Focus Tubes/ Filaments)
Small filaments produce ____ - 0.5mm focal spots.
0.1
What is the most common cause of tube failure which in turn leads to filament breakdown?
Tungsten Vaporization
The stator is powered by an induction motor and creates a magnetic field which measures in between _______ - ________ RPM.
3,600-10,000
Pitting due to slow rotation and exceeding heat capacity is an example of:
Anode Failure
The physical area of the focal track that is impacted is called:
Actual focal spot
The area of the focal spot that is projected out of the tube toward the object being radiographed is called;
Effective
The angling of the target area on the anode is called:
Line focus principle
As the anode angle decreases, the ______ focal spot decreases.
Effective
The only advantage of a large focal spot is increased _______ _________.
Heat Capacity
The blurring on the edge of an organ or bone due to the size of the focal spot is called:
Penumbra
Kvp, tube current, voltage wave form, length of exposure and number of exposures determine the amount of heat generated and expressed in:
Heat Units (HU)
In order to calculate the total Anode Cooling Factor expressed in HU, one must mulitply:
Kv x mAs x voltage waveform factor
The Voltage Waveform factor for single phase is:
1.00
The Voltage Waveform factor for Triple Phase 6 Pulse is:
1.35
The Voltage Waveform factor for Triple Phase 12 Pulse is:
1.41
The Voltage Waveform factor Triple Phase High Frequency is:
1.45
A reduction in radiation intensity results from a complete or partial loss of x-ray photon energy as it passes through matter. This is called:
Attenuation
A complete loss of energy is a form of attenuation termed:
Absorption
High energy photons have _____ attenuation values.
Lower
Low energy photons have _______ attenuation values.
Higher
High energy electrons interact with the _______.
Nuclei
The energy of photons that changes as it passes through the body is called:
Half Value Layer (HVL)
Materials with a high z# are more dense and have a higher ________ value.
Attenuation value
In every 4 cm of tissue the xray intensity is cut by _______ to the original value.
Half
An incident electron that is absorbed, excites the atom, releases, and changes direction without losing any kinetic energy is called:
(It only occurs with incident electrons with about 10keV***)
Coherent Scattering
In the Photoelectric effect, an xray photon is completely absorbed by an ______ shell electron.
Inner
What is the transfer calculation equation for the Photoelectric effect?
Ei=Eb+Eke
Which kvp setting is more likely to cause a Photoelectric effect; low or high?
Low
In the Compton effect, an electron changes it’s direction, loses energy and becomes ionized. This ionization causes the electron to eject from the _______ SHELL.
OUTTER
The Compton effect transfer calculation equation is:
Ei= Es + Eb + Eke
In Pair Production a _______ is attracted to a negative electron and both undergo an ________ effect.
Not Diagnostic; Happens in RAD Therapy such as PET Scans***
Positron
Annihilation
In Photo Disintegration the atomic ______ breaks down due to an incident photon having an energy greater than 10 meV.
Not Diagnostic***
Nucleus
What is the study of stationary or resting electric charges?
An object is said to be electrified if it has too few electrons*
Electrostatics
_______ is caused by Friction, Contact, Induction.
Electrification
What are the 5 Laws of Electrostatics?
Right Inside Directly Centered More
- Repulsion/ Attraction
- Inverse square
- Distribution
- Concentration
- Motion
Describe the inverse square law in Electrostatics:
f=k x q1 x q2/ d^2
Low Energy Force.. Greater Distance
High Energy Force.. Shorter Distance
Force is inversely proportional to the square of the distance.
Electric charges reside on external surfaces of conductors.. What law is this?
Distribution
Charges are greater on a curved surface of a conductor.. What law is this?
Concentration
Only negative charges can move in solid conductors.. What law is this?
Motion
(V=I x R) Voltage is equal to the product of Current (I, Amps, A) flowing through a conductor and the Resistance of the conductor (R). This is called _______ law.
Ohm’s
Which type of electric material allows electrons to flow easy?
Conductors
Which type of electric material are very poor conductors?
Insulators
Which electric material allows electrons to pass through little by little through a gap?
Semiconductors
Superconductors have ______ resistance.
0
Weakly repelled materials such as water or plastic are called:
Diamagnetic
Weakly attracted materials such as Gadolinium (MRI Contrast) are called:
Paramagnetic
Strongly magnetized materials such as iron, nickel, or cobalt are called:
Ferromagnetic
The process by which an object or material is magnetized by an external magnetic field is called:
Magnetic Induction
The relationship between current, ferromagnetic cores and changing magnetic fields is called:
Electromagnetic Induction
What produces electricity (converts mechanical energy to electrical energy)?
Ex: Dynamo
Components: Magnet & Wire Loop
Generator
What converts electrical energy to mechanical energy?
Components: Magnet, Wireloop, Source of Electricity
Motor
The flow of electric charges reverses direction.. This is an example of _____.
Two loops*
Alternating Current
The flow of electric charges are in only one direction.. This is called ______.
One loop*
Direct Current
