RT 52A quiz 1

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RT 52A quiz 1
2012-10-03 01:56:52
RT 52A quiz

RT 52A quiz 1
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  1. An atom is made up of?
    • -Protons +
    • -Neutrons
    • -Electrons -
  2. Where are the Protons and Neutrons located?
  3. What does the Proton number indicate?
    Indicates the Atomic number or Z number
  4. The number of Protons and Neutrons indicate?
    Mass number
  5. Where is the Electrons located?
    Located in shells or energy levels around the nucleus
  6. What does it mean If an electron is close to the nucleus?
    The more tightly it is bound
  7. Define: Radiography
    The study of the diagnostic use of ionizing radiation
  8. Define: Diagnostic
    A tool used to make a diagnosis
  9. Define:Ionization
    - 3 example
    Any radiation with sufficient energy to remove an orbital electron from the atom that it interacts with.

    • - X-rays,
    • - Gamma Rays
    • - Ultraviolet light
  10. The number if proton in the nucleus of an atom is equal to?
    Equal to the number of electron
  11. Atoms are electrically neutral, what happen if the atom gains or loses an electron?
    the atom becomes either negative or positively charged
  12. Name three natural environmental radiation and provide example.
    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 
  13. What is a mad made radiation?
    X-ray and results in an annual dose of 60-65 mrem
  14. What is mA?

    -milli: 1/1000

    - 75 mA = 75/1000 = .075
  15. What is mAs?
    The product of milliamperage and time (s).

    -Correspond to the number of x-rays created on the x-ray tube 
  16. what is kV?
    -UNit used for electric potential and electromotive force.

    -kilo = 1000

    -75kV = 75000 volts

    - the penetrating power of the beam
  17. Define: Exposure
    Measure of the ionization produced in air by x-rays
  18. Define: Absorbed dose
    The amount of energy per unit mass absorbed by an irradiated object
  19. Define: Equivalent dose
    • The product of the absorbed dose in a tissue or organ and its associated radiation weighting factor (W  )
    •                            R
  20. Define: Effective dose
    • 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
  21. What is the Customary unit and SI unit for exposure?
    • CU= name:Roentgen     symbol: R
    • SI= name: Air kerma     symbol: Gy
    •                                                       a
  22. What is the CU and SI units for absorbed dose?
    • CU= name: RAD    symbol: RAD
    • SI= name: Gray    symbol: Gy
    •                                               t 
  23. What is the CU and SI units for Effective dose?
    • CU= name: REM        symbol: REM
    • SI=  name: Sievert     symbol: Sv
  24. Conversion Factors
    CU units                                         SI units

    • R                         x   .01       =       Gy
    •                                                          a 
    • RAD                     x   .01       =       Gy 
    •                                                          t
    • REM                     x   .01       =       SV
  25. Define: ratio
    Express the mathematical relationship between similar quantities
  26. define: proportion

    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.
  27. Name two examples of Particulate Ionizing Radiation.
    • 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
  28. Name two examples of Electromagnetic of Ionizing radiation.
    • 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
  29. Electromagnetic Radiation: Photons in relation to Electromagnetic Radiation.
    • 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
  30. Define: Frequency
    • - 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
  31. Define: wavelength
    • - The distance from one crest to another or one valley to another.
    •      - unit of measure is meter 
  32. Frequency and wave length are ____ proportional.
    • - inversely
    •  ex: As frequency increases wavelength will decrease
  33. Define: Amplitude
    It is 1/2 the range from crest to valley
  34. What happens to wavelength when frequency is high?
    wavelength will be short or low
  35. Photon E is ____ proportional to the frequency of its wavelngth.
  36. An x-ray beam of great penetrating power consists of photons that have:
    • -high energy
    • -high frequency
    • -short wavelength