Basic Concept Of Radiation Flashcards
Emission of energy by atoms
Radiation
Flow of atomic and subatomic particles w/ characterized heat
Radiation
Travel in a form of a particle possesinh either mass or charge can cause ionization
Particulate radiation
Disturbance in space in the form of wave
Electromagnetic radiation
Form of energy that is a result of eletric and magnetism disturbances is space produced by charge acceleration
Electromagnetc energy
Electromagentic radiation behaves as a wave and as particle
Wave particle duality
Disturbances in a medium
Waves
No medium required
EM waves
EM wave travel in a form of a
Sine wave
Speed at which the wave travels
Velocity (c)
EMR travels at
Speed of light
Speed of light
3x10^8 m/s
186,000 mi/s
Distance between two successive crest, measured in meters/angstrom
Wavelength
Number of waves passes a particular time
Frequency
Frecuency is measured by
Hz
Cycles/sec
Energy is _______[ to frquency
Directly proportional
Speed of EMR is _________
Contant at the speed of light
Energy is _______ to wagelength
Inversely proportional
Act as small bundle of energy
Photon/quantum
Photon energy (E ) =
hv
Planck’s contant
4.135x10^-15 eV/sec
Produced when high velocity electrons ar decelerated during interaction
Xrays
Xreys for medical imaging ranges
10 keV to 100 kEv
Wavelength 10^-10 to 10^-11 meters
Photon is mometarily absorbed by shell electron or atom as a whole
Classical scattering
Photon interacts with outer shell electron of the target atom
Compton effect / compton scattering
Outer shell electron and ejects it
Compton electron
The greater the energy lost, _______ divergence from its original path
Greater
Interaction with the inner shell electron
Photoelectric absorption
Energy will travel in a different direction
Scatter radiation
The ejected electron
Photoelectron
Transition releases energy equivalent to the difference between the binding energies of the shells participating in the evnt
Characteristic radiation
As kvp increases
Total number of photons increases
Photoelectric interaction decreases
Compton scattering increases
Incident photon comes close to the nuclear field
Pair production
Energy on pair production
> 1.02 MeV
Incident photon strikes the nucleus of the atom
Photodisintegration
Photodisintegration energy is above
10 MeV
Result of the different atomic number of the material that make up patient’s body
Density differences
Xray incident on a specific part of the patient’s body causing the film to darken
Differential absorption
Five radiographic density
Air Fat Water Bone Metal
Most radiolucent, appears dark on the radiographic image
Air
Most radiopaque appears whitest in the image
Metal
Capacity of matter to obstruct the transmission of radiant energy
Radiopaque
Permeable to radiation permeable to radiation or penetrable by xray
Radiolucent
Xray differential absorption
Pass through matter w/o absoption
Absorb
Scattered
5 basic interaction of radiation with matter
classical scattering photoelectric effect compton effect pair production photodisintegration
classical scattering requires low energy radiation of
1
Compton effect requires energy
above 10 MeV
pair production produces _______ with 0.51 MeV
positron
electron
