RT 52A quiz 1

• -Protons +
• -Neutrons
• -Electrons -

Nucleus

Indicates the Atomic number or Z number

Mass number

Located in shells or energy levels around the nucleus

The more tightly it is bound

The study of the diagnostic use of ionizing radiation

A tool used to make a diagnosis

Any radiation with sufficient energy to remove an orbital electron from the atom that it interacts with.

• - X-rays,
• - Gamma Rays
• - Ultraviolet light

Equal to the number of electron

the atom becomes either negative or positively charged

Cosmic rays: Emitted by sun and stars

• Terrestrial:
• -Uranium: found in the Earth
• -Radon: gas produced by the natural decay of Uranium
•        -Is the largest source of natural radiation
•        -Concrete, bricks, gypsum board

• -Internally deposited radionuclides
•        -Natural metabolites; have always been with us.
•        -Results in an annual dose of approx. 300 mrem 

X-ray and results in an annual dose of 60-65 mrem

-milliamperage

-milli: 1/1000

- 75 mA = 75/1000 = .075

The product of milliamperage and time (s).

-Correspond to the number of x-rays created on the x-ray tube 

-UNit used for electric potential and electromotive force.

-kilo = 1000

-75kV = 75000 volts

- the penetrating power of the beam

Measure of the ionization produced in air by x-rays

The amount of energy per unit mass absorbed by an irradiated object

• The product of the absorbed dose in a tissue or organ and its associated radiation weighting factor (W  )
•                            R

• The measure of the overall risk of exposure to ionizaing radiation. Take into effect the type of radiation and its (W  ) and the organ
•                                       R
• exposed and its weighting factor (W  ).
•                                                   T

• CU= name:Roentgen     symbol: R
• SI= name: Air kerma     symbol: Gy
•                                                       a

• CU= name: RAD    symbol: RAD
• SI= name: Gray    symbol: Gy
•                                               t 

• CU= name: REM        symbol: REM
• SI=  name: Sievert     symbol: Sv

CU units                                         SI units

• R                         x   .01       =       Gy
•                                                          a 
• RAD                     x   .01       =       Gy 
•                                                          t
• REM                     x   .01       =       SV

Express the mathematical relationship between similar quantities

Expresses the relationship of one ratio to another.

- Direct proportion: if A is high, B is high.

- Indirect proportion: if A is high, B is low.

• Particulate:
• - Alpha radiation: -mass # of 4
•                           - +2
•                           - emitted from nucleus of heavy metals
•                           - short range in matter
•                           - sever damage w/in the body

• - Beta radiation: -Mass # of 10
•                          - (-)1
•                          - Emitted from nucleus of radioactive atom
•                         - more  penetrating in matter

• Electromagnetic:
• - Gamma radiation: -mass # of 10
•                               -no charge
•                               -emitted from nucleus of radioisotope 
•                               - have unlimited rage in matter

• - X-rays:                - Mass # of 0
•                              - no charge
•                              - Originates in energy levesl surrounding atom
•                              - Have unlimited range in matter

• Photon:-the smallest quantity of EM radiation
•             -Travel at the speed of light
•             - AKA: quantum
•             - unit of measure: volt: in radiology, it is kilovolt. 1kV= 1000 volts
•             -photons surround by electrical and magnetic fields called sine waves

• - The # of crests or valleys that pass an observer per unit of time; the rise and fall of sine wave
• - Measured in cycles/sec. : unit of measure is Hertz. 1Hz = 1 cycle/sec

• - The distance from one crest to another or one valley to another.
•      - unit of measure is meter 

• - inversely
•  ex: As frequency increases wavelength will decrease

It is 1/2 the range from crest to valley

wavelength will be short or low

directly

• -high energy
• -high frequency
• -short wavelength