physics ch. 1,2&3 Flashcards
who discovered x-ray?
Dr. Wilhelm Conrad Roentgen
when was x ray discovered? where?
nov. 8, 1895 ;Germany
how was x ray discovered?
Crookes tube covered with black paper testing light. which created a glow on a barium platinocyanide plate.
how fast does an x ray travel?
speed of light
how fast do electrons travel?
depends on kVp
what is the Crookes tube? when was is discovered?
gas-filled tube and was created in 1895
what is the Coolidge tube and when was it discovered?
vacuum tube with cathode (linked to the snook making high kVp possible) 1913
who created the stationary grid? when?
Gustav Bucky (German) 1913
who created the reciprocating grid? when?
Potter; 1921
what was the first X-ray ever taken
hand X-ray of Mrs. Berta Roentgen
when&what was the first X-ray taken in the US?
young boy’s broke wrist; in New Hampshire, 1896
What makes up matter?
Atoms and molecules
Atom
Neils Bohr (1918) = protons and neutrons held together in the nucleus surrounded by electrons
Molecules
two or more atoms held together chemically
how can you find the # of protons in an Atom ?
the Z# (atomic #)
how many electrons can the outer most shell have?
8 electrons
how can you find the number of electrons in each shell?
2N^2
Be
Beryllium
C
Carbon
O
Oxygen
Ca
Calcium
Fe
Iron
Al
Aluminium
Si
silicon
Ni
Nickel
Cu
copper
Mo
Molybdenum
Ru
Ruthenium
Rh
Rhodium
Ag
silver
Sn
Tin
I
Iodine
Ba
Barium
W
Tungsten
Re
Rhenium
Au
Gold
Pb
Lead
U
Uranium
Binding Energy
Strength of electrons attachment to the nucleus. closer to the nucleus= greater binding energy
potential Energy
stored energy by virtue of position. the further from the nucleus the greater potential energy
kinetic energy is?
energy in motion; energy expanded
thermal energy
Heat
Electromagnetic energy
X-ray converts kinetic energy into electromagnetic energy in the form of X-ray
E=mc^2
energy= mass X the speed of light^2
what is the speed of light
186,000 MILES PER SEC.
3x10^8 m/sec
3x10^10 cm/sec
newtons first law of motion
body at rest will remain at restore will continue to move in a straight line unless it is disturbed
newtons Second law of motion
Force= Mass X Acceleration
do electrons move in a straight line?
No
what is the formula for electrons according do newtons second law of motion?
F=mV^2/r
what is ionization
Ionization is when an orbiting electron is removed from orbit creating an ion pair (+ charged atom & a - charged free electron
types of ionizing radiation
particulate radiation and Electromagnetic Radiation
Particulate radiation create what?
Alpha and Beta particles
Electromagnetic radiation create what ?
Gamma rays and X-rays
what are Alpha particles
2 Protons and 2 neutrons (+), large so they can not penetrate very far
what sub-atomic particle has the highest LET?
Alpha
What sub-atomic particle has the highest penetration ?
Beta
whats the minimum protection for Alpha particles?
Paper
whats the minimum protection for a Beta particle?
aluminum , wood 1Cm thick or 1 mm thick lead
what is the diff. between X-ray and Gamma ray?
their origin
X- ray origin?
inner shell electron interaction
Gamma ray origin?
nucleus interaction
what is the minimum effective dose for a student?
1 mSv annually (.1 rem)
what is the relationship between wavelength and frequency?
Inverse
what is the wavelength formula
Velocity= frequency X wavelength
Velocity
V= d/t ; m/s
Force
F=ma ; N
Work
Work= Fd ;J
Power
P=work/t ;W
what is a (R)
roentgen; coulomb/kilogram (C/kg)
what is (rad)
radiation absorbed dose; gray (Gy)
what is a (rem)
Radiation equivalent man sievert (Sv)
what is a (ci)
Curie; Becquerel (Bq)
what is the Gy used for?
used to quantify the biologic effects of radiation on humans and animals
what is the Sv used for?
used to quantify occupational exposure; effective dose; biological effectiveness dose
the curie/Becquerel is used for?
used to quantify Radioactivity; quantity of radioactive material not its effects on radiation being emitted
1 rem is_____mSv
10mSv
100 mrem=_____mSv
1 mSv
Radiolucent
radiation can penetrate through it (soft tissue)
Radiopaque
radiation gets absorbed by it (bone)
inverse square law
the intensity of the new distance will be the inverse of the distance squared (indirectly related and not proportional)
what filter should be added when working with 50 kVp and below
1 mm Al/eq
what filter should be added when working with 50-70 kVp
1.5 mm Al/eq
what filter should be used when working with above 70 kVp
2.5 mm Al/eq
what is the magnification formula
SID/SOD