RT 20 Final 2014 Word Scramble
|
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Question | Answer |
The strength of attachment of an electron to the nucleus | electron binding energy |
An x-ray photon is a quantum of | electromagnetic energy |
is one half the range from crest to valley over which the sine wave varies | amplitude |
the number of wavelengths that pass a point of observation per second | Frequency |
the properties of electromagnetic energy include | frequency, wavelength, velocity, and amplitude. |
the reduction in intensity htat results from scattering and absorption | attenuation |
structures that absorb x-rays are called | radiopaque |
structures that transmit x-rays are called | radiolucent |
the study of stationary electric charges | electrostatics |
the quantity of matter as described by its energy equivalence | Mass (Kg) |
the ability to do work | energy |
energy is measured in | Joules (j) |
In radiology, the Unit or energy is oftened used is known as | Electron Volt (eV) |
Theory first described by Einsten that matter and energy are interchangeable | Theory of Relativity |
energy emitted and transferred through space | radiation |
Natural environmental radiation annual dose | 3 mSv |
currently accepted approx. annual dose resulting from medical applications of ionizing radiation is | 3.2 mSv |
X-rays accidentally discovered by Wilhem Roentgen on | Nov. 8, 1895 |
roentgen discovered x-rays by while experimenting with | a type of crookes tube while trying to visualize cathode rays. |
3 general types of x-ray exams | Radiography, fluoroscopy, and computed tomography. |
to provide an x-ray beam that is satisfactory for imaging,you must supply an x-ray tube with a | high voltage and an electric current |
x-ray voltages measure in | kilovolt peak kVp |
the first recorded death from x-ray in 1904 was | thomas edisons research assistant clarence Dally. |
one unit of negative electric charge, fixed orbits, and atomic mass number is 0 | electron |
one unit of positive electric chargem atomic mass number is 1 | proton |
carries no charge, atomic mass number is 1 | neutron |
unstable atoms that have an unstable nucleus that spontaneously emits particles and energy ans transforms itself into another atom in the process | radioactive decay |
2 ways for radioisotopes to decay are by | beta (more frequent) and alpha emissions. |
the time for a quanitity of radioactivity to be reduced to one half its original value is | radioactive half life |
radioactive material never quite reaches | 0 |
x-rays and gamma rays are called_____ and have no_____or______ | photons, charge or mass. |
travel at the speed of light and are considered enery disturbances in space. | photons |
only difference between x-rays and gamma rays is | thier origin |
electromagnetic energy exists over a wide range called an | energy continuum |
speed and direction in which an object moves. | velocity |
the energy of a photon is ______ perportional to its frequancy | directly |
unlike charges_____: like charges______ | attract,repel |
law that states when force is strong close together and decreases rapidly when separates | coulomb's law |
electric charge is distributed______ throughout a surface. | uniformly |
electric charge of a conductor is concentrated along | sharpest curvature of the surface |
the study of electric charges in motion | electrodynamics |
any substance in which electrons flow easily | conductor |
any material that does not allow electron flow | insulator |
materials that under some conditions act as an insulator and in other conditions act as a conductor | semiconductor |
the property of some materials such as titanium to exibit no resistance to electron flow below a critical temperature | superconductor |
the three principal parts of an x-ray imaging system | x-ray tube, operating console, and high voltage generator |
refers to the number of x-rays or the intensity of the x-ray beam | radiation guantity (mGya) |
refers to the penatrability of the x-ray beam and is expressed in Kilovolt peak or more precisely, HVL | Radiation quality |
measures he voltage provided to the x-ray imaging system and adjusts that voltage to precisely 220 V. | Line Compensator |
has a single winding and is designed to supply a precise voltage to the filament circuit and to the high-voltage circuit of the x-ray imaging system. | Autotransformer |
Determines the quality of the x-ray beam | kVp |
the x-ray tube current crossing from cathode to anode is measured in | milliamperes mA |
the number of electrons emitted bt the filament is determined by | the temperature of the filament |
the filament temperature is controlled by the | filament current |
is the release of electrons from a heated filament | thermionic emission |
guards against exessive radiation exposure and electric shock, mechanical support, and rough handling | protective housing |
x ray that escape through the protective housing are called | leakage radiation |
when x-rays are produced they are emitted isotropically, that is they are emitted | with equal intensity in all directions |
_____or_____ ______ matiains a vacuum inside the tube that alows for more efficient x-ray production and longer tube life | glass or metal enclosure |
the negative side of the x-ray tube | cathode |
two primary parts of the cathode are | filament and focusing cup |
a coil of wire approx 2mm in diameter and 1 to 2 cm long usually made of tungsten | filament |
the most common cause for tube failure is | tungsten vaporization with deposition on the inside of the glass enclosure. |
is negatively charged so that it electrostatically congines the electron beam to a small area of the anode, where the filament is embedded | focusing cup |
a cloud of electrons formed around the filament that makes it difficult for subsequent electrons to be emitted bt teh filament, | space charge |
the positive side of the x ray tube, conducts electricity, radiates heat, and contains the target | anode |
atomic number of tungsten is | 74 |
the atomic number of molybdenum | 42 |
the atomic number of rhodium | 45 |
results in a an effective focal spot size being much less than the actual focal spot size | line focus principle |
results in a smaller effective focal spot and less radiation intensity on the anode side of the x-ray beam | heel affect |
The most frequent cause of abrubt tube failure is | electrons arcing from the filament to the enclosure because of vaporized tungsten. |
energy in motion | kinetic energy |
electrons travel from | cathode to anode |
electrons traveling from cathode to anode constitute the x-ray tube current and are sometimes called | projectile electrons |
approximately 99% of the kinetic energy of projectile electrons is converted to | heat |
approximately 1% of the projectile electron kinetic energy is used for | x-ray production |
in the diagnostic range, heat production increases directly with increasing | kVp |
the production of heat in the anode increases directly with increasing | x-ray tube current |
if the projectile electron interacts with an inner shell electron of the target atom rather than an outer shell electron | characteristic x-rays can be produced |
are emitted when an outer shell electron fills and inner shell void | charactaristic x-rays |
only the ____ charactaristic x-rays of tungsten are useful for imaging | K |
produced when a projectile electron is slowed bt the nuclear field of a target atom nucleus | bremsstrahlung x-rays |
in the diagnostic range, most x-rays are | bremstrahlung x-rays |
bremsstralung x-rays have a range of energies and form a | continuous emission spectrum |
max x-ray energy is associated with the minimum | x-ray wavelength |
A change in mA or mAs results in a proportional change in the_______ of the xray emission spectrum | amplitude |
how does filtration effect the emission spectrum? | Decreases amplitude shifts to right |
if filter thickness is reduced, x ray is | increased |
changes in ________ result in Directly proportional changes in the amplitude of the emission | MA/time |
efficiancy of x-ray production increases as_____ increases | kvp |
Created by:
1820547421
Popular Physics sets