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Chap 1&2
Imaging Equipment. Chap 1 Concepts, Chap 2 Structure
Question | Answer |
---|---|
____ is anything that occupies space | matter |
the fundamental building blocks of matter are | atoms and molecules |
prefix kilo stands for ______. So, a kilogram is equal to how many grams? | 1000;1000 |
International system (SI) energy is measured in _____. In radiology the unit ______ is often used. | Joules (J). Electron volt (eV) |
Potential is the ability | to do work by virtue of position |
energy of motion is | kinetic |
an example of chemical energy is | dynamite, or metabolizing food (energy released by a chemical reaction) |
Energy of motion at the molecular level is | thermal energy (heat) |
Nuclear energy is | energy that is contained within the nucleus of an atom |
Theory of relativity? | matter and energy are interchangeable |
Mass-energy equivalence equation is | E=mc^2 (E is energy, m is mass, c is velocity/speed of the radiation) |
Radiation is | the transfer of energy |
Ionizing radiation is any radiation capable of | removing an orbital electron from the atom with which it interacts. |
The orbitral electron and the atom from which it was separated are called | an ion pair. |
Two main categories of sources of ionizing radiation | natural and manmade |
Natural environmental radiation results in an annual dose of approx. ________. Man-made radiation results in _________ annually. | 3 millisieverts (mSv). 3.2 mSv. |
natural radiation consists of what 4 components: | cosmic rays, terrestrial rad, internally deposited radionuclides, and radon. |
______ are particulate and elctromagnetic rad emitted by the sun and stars | cosmic rays |
______ rad results from deposits of uranium, thorium, and other radionuclides in the Earth. | terrestrial |
The largest source of natural radiation is | radon |
radon is a radioactive gas that is produced by | the natural decay of uranium. |
____ emits alpha particles, which are not penetrating, and therefore contributes a radiation dose only to the lung | radon |
Wilhelm Roentgen was experimenting and discovered x-rays when? | november 8, 1895 |
Roentgen produced and published the first medical x-ray image in ____, it was an image of what? | early 1896 (feb?), his wife's hand |
x-ray voltages are measured in ______. | kilovolt peak (kVp) |
one kilovolt (kV) is equal to ____ V of electric potential | 1000 |
X-ray currents are measured in _____, where the ____ is a measure of electric current. | milliampere (mA), ampere (A) is a measure of electrical current. (Milli is prefix for 1/1000.) |
When was the fluoroscope developed? | 1898 by Thomas Edison. |
Who is Clarence Dally? Why is he important? | Assistant and long time friend of Edison. He experienced a severe x-ray burn that resulted in his death in 1904. He is counted as the first x-ray fatality in the U.S. |
William D. Coolidge unveiled his hot-cathode x-ray tube to the medical community when? | 1913 |
X-ray tubes used today are refinements of the ___ tube. What tube did Roentgen discover x-rays with? | coolidge. Crookes. |
Radiology emerged as a medical specialty because of the _____ and the ________. | Snook transformer and the Coolidge x-ray tube. |
When did Hounsfield complete development of the first CT system? | 1973 |
When was ASRT founded? | 1920 |
Physics is the study of | matter and energy |
the 3 base quantities of measurement are | mass, length, time |
The second (s) is based on the vibration of atoms of | cesium |
Every measurement has two parts: _____ and a _____ | magnitude and a unit. (ex- SID is 100cm. Magnitude is 100, unit of measurement is the cm) |
Exposure....? Number of ionizations in given quantity of air: ?? Units? | 1R = 258 x 10^-4 c/kg |
_____ is how fast something is moving, or, the rate of change of its position with time | velocity/speed |
Units of velocity in SI are | meters per second (m/s) |
Equation for velocity is: | v=d/t. d is distantce traveled in time t. |
The rate of change of velocity with time is ________ | acceleration. (how quickly or slowly the velocity is changing) |
Because acceleration is velocity divided by time, the unit is | meters per second squared (m/s^2) |
Newtons fundamental laws of motion: | interia, force, action/reaction |
Newtons first fundamental law of motion: | inertia- a body will stay at rest or will continue to move with constant velocity in a straight line unless acted on by an external force. |
Newtons first fundamental law: (simple) | If no force acts on an object, there will be no acceleration.. once in motion however, it will continue to move forever, even when the pushing force is removed, unless an opposing force is present. |
Newtons second law: | Force- the force (F) that acts on an object is equal to the mass (m) of the object multiplied by the acceleration (a) produced. (If a body of mass has an acceleration, then the force on it is given by the mass times the acceleration) |
Newtons third law: | Action/reaction- for every action, there is an equal and opposite reaction. ("action" was newtons word for "force".. if you push on a heavy block, the block will push back with same force you apply) |
The weight of an object is equal to | the product of its mass and the acceleration of gravity. |
The product of the mass of an object and its velocity is called | momentum |
Work is the product of ___ and ____. In mathematical terms the unit of work is the | Force and distance. Joule. |
_________ is the rate of doing work | power. |
2 forms of mechanical energy: | kinetic (associated with motion) and potential (stored) |
3 ways heat is transferred: | conduction, convection, radiation. |
_____ is the transfer of heat through a material of by touching | conduction. ex- when a hot object and a cold object are placed in contact. |
______ is the transfer of "hot" molecules in a gas or liquid from one place to another. | Convection. ex- steam radiator or forced air furnace heats a room. |
____ is the transfew of heat by the emission of infrared radiation. | thermal radiation. ex- reddish glow emitted by hot objects. |
______ elements have been identified, _____ are naturally occuring and ___ have been artificially produced. | 118, 92, 26 |
___ is the smallest particle that has all the properties of _____ | an atom, an element |
Elements are grouped based on what | by the placement of electrons in each atom? |
Elements in the same ____ reach chemically in a similar fashion and have similar physical properties | group |
Who introduced the nuclear atom model? Who improved that model, like a mini solar system? | rutherford, bohr. |
which model most accurately describes the details of the atoms atomic structure? | quantum chromodynamics (QCD) although bohr represents best way to picture atom |
Nucleons - ______ and _____- are composed of ______ that are held together by ____. | protons and neutrons, quarks, gluons. |
Fundamental particles of an atom? | protons, neutrons, electrons. |
Difference between atomic mass units and atomic mass numbers? | When precision is not necessary, mass numbers is used, its a system of whole numbers. |
2 types of nucleons? | protons and neutrons |
The number of _____ ultimately determines the chemical behavior of an atom | protons |
The number of ______ determines the chemical element | protons |
Atoms that have the same # of protons, but different neutrons are _____ | isotopes (same atomic #, different atomic mass) |
The force that keeps an electron in orbit is the ____________ force. The _________ force makes it so electrons maintain their distance from the nucleus. | centripetal, centrifugal |
True or false: the greater the the total # of e- in an atom, the more tightly each is bound. | T. ( the larger and more complex the atom is, the higher the Eb for e- in any shell) |
Atomic number is represented by ___, atomic mass is represented by ___. | Z, A. |
Atomic number (Z) is what? Atomic mass (A) is what? | # of protons is Z, # of protons plus neutrons is A. |
Atomic nuclei that have the same atomic mass # but different atomic #s are _______ | isobars. (......different # of protons and neutrons, but have the same TOTAL # of nucleons)... (opposite of isotopes) |
Atoms that have the same # of neutrons but different # of protons are _____ | isotones. (Diff atomic # and diff mass # but constant value for the quantity A-Z.... isotones have are atoms with the same # of neutrons..) |
_____ have the same atomic number and the same atomic mass number. | Isomer. |
isotoPe- same Proton. isobAr- same A (atomic mass). isotoNe- same Neutron. isoMer- Metastable | |
What is a compound? | any quantity of one type of molecule |
Covalent bonding is characterized by | the sharing of electrons |
Ionic bonding is characterized by | giving up an electron, resulting in opposite electrostatic charges. |
The smallest particle of an element is _______, the smallest particle of a compound is _____ | an atom, a molecule. |
__________ is the spontaneous emission of particles and energy in order to become stable | radioactivity |
Some isotopes are stable, but others can emit, or kick out, subatomic particles to reach a more stable, lower-energy, configuration. Such isotopes are called ______, and the process in which they release particles and energy is known as _____. | radioisotopes, decay. |
Radioisotopes can decay to stability in many ways, but two are: | beta and alpha emission |
During ____ emission, an e- created in the nucleus is ejected and escapes from the atom. | Beta |
The result of ____ emission is to increase the Z# by 1 while the A# remains the same.. changing to a different atom. | Beta. (looses an e-, simultaneously a neutron transforms to a proton) |
The ____ particle consists of two protons and two neutrons, with an atomic mass # of 4. | alpha |
What emession (beta or alpha) looses 2 units of positive charge and four units of mass? (chemically different and lighter by 4 amu) | alpha |
Which emission occurs more frequently? | beta. only heavy radioisotopes are capable of alpha. |
What is radioactive half-life? | the half life of a radioisotope is the time required for a quantity of radioactivity to be reduced to one-half its original value. |
*Air kerma is the | kinetic energy transferred from photons to e- during ionization and excitation. |
Air kerma is measured in, where 1 ___ is 1 ____ | joules per kilogram where 1J/kg is 1 gray (Gya) |
Air kerma (Gya) is the unit of | radiation exposure (can also be mGya in SI?) |
The gray (Gyt) is the unit of | radiation absorbed dose (rad) |
The _______ is the unit of occupational radiation exposure and effective dose | sievert (Sv) |
The ____ is the unit of quantity of radioactive material, not the radiation emitted by that material | Becquerel (Bq) |
All ionizing radiation can be classified into two categories: | particulate and electromagnetic radiation |
At rest, this type of ionizing radiation cannot cause ionization | particulate |
two types of particulate radiation? | alpha and beta particles |
___ particles contain 2 neutrons and 2 protons, no e- which makes them dangerous due to the positive charge. ____ particles is an e- emitted from the nucleus of a radioactive atom. | alpha, beta. |
The _____ on the table indicate the # of e- in outermost shell. The ___ have the same # of orbital shells. | groups, periods. |
Some atoms, which contain too many or too few neutrons, can disinegrate. this is called | radioactivity |