X-Ray Physics Review part 3 Flashcards
Name the guy from 1913 who described the atom as a “mini solar system”
Niels Bohr
Do all electrons in an atom have the same binding energy?
No. Electrons closer to the nucleus have higher bonding energies
Are radio waves, TV, FM, visible light, ultraviolet light, x-rays, and gamma-rays all really forms of electromagnetic radiation?
Why yes, they are
Does all electromagnetic radiation travel at the speed of light?
Yes
What is meant by wavelength?
It expresses a measurement of either crest to crest or valley to valley
What is meany by frequency in electromagnetic radiation?
It is the number of wavelengths passing by a certain point per second.
Hertz (Hz) = ____ cycle(s)/second
1 Hertz is 1 cycle per second
As the frequency of electromagnetic radiation increased the energy ______.
increases. They are directly proportional
Which shell is closest to the nucleus? (K-Shell, L-Shell, M-Shell, or N-Shell)
K-Shell
This “a” word refers to the process of x-rays being stopped within the subject.
Absorption
This “t” word refers to x-rays that pass through a subject without interacting.
Transmission
What are the two processes that account for attenuation of the x-ray beam?
absorption and scatter
Lead is used in protective garments because it _____ x-rays.
absorbes
30% of the primary beam is absorbed and 10% is scattered. How much of the beam was attenuated?
40%
What are the three possible outcomes when diagnostic x-rays enter a subject?
Transmission, scatter (classical or compton), or absorption
What are two other names for “classical” scatter?
coherent or unmodified scattering
Does ionization occur with Classical scatter?
No. The x-rays are too low energy to cause ionization. They just vibrate the atom which causes it to release a secondary photon.
What is the relationship between the angle of the compton scatter and it’s energy?
The greater the angle, the lower the energy. 180 degrees has the lowest energy
Which type of scatter (which is worse) that causes film fog and occupational exposure?
compton
What is the scientific name for the process of ‘absorption’?
Photelectric absorption or “photoelectic effect”
When the x-ray photon is absorbed in the photoelectric effect does it knock out an inner shell or outer shell electron from the subject atom?
Inner shell (when the photo knocks out an outer shell electron it produces compton scatter)
What “p” effect is reponsible for the “white” on an x-ray image?
Photoelectric effect (absorption)
For photoelectric effect to occur the incident photon needs to have _____ higher energy than the binding energy of that inner shell electron.
just slightly (the chance of photoelectric effect drops off as the incident photons energy becomes much higher than the electrons)
At lower kVp there is ____ photoelectric effect and ____ compton scatter
More and Less
At higher kVp there is ___ photoelectric effect and ____ compton scatter
less and more
Photoelectric absorption is more likely to occur with ____. (lower atomic numbers, higher atomic numbers, very high energy photons).
higher atomic numbers
The electron ejected during a Compton interaction is called the _____.
Recoil or compton electron
