MMET 402 EXAM III QUESTIONS AND
ANSWERS
An X-ray film or IP having wide latitude (dynamic range) also has, by definition: -
Answer- low contrast
Thin sheets of lead foils in intimate contact with IP during exposure increase image
density because they: - Answer- emit electrons when exposed to X- and gamma
radiation which help darken the image
The adjustment of tube current in conventional X-ray tube circuits is made by: - Answer-
adjusting the filament heating current
The range of thickness over which densities are obtained that are satisfactory for
interpretation is a measure of the: - Answer- latitude (dynamic range) of a radiograph
Two isotropic sources of a given strength have two different specific activity values. The
source with the higher specific activity value will: - Answer- have a smaller physical size
than the source with a lower specific activity
After traveling through two half-value layers, the incident radiation has been reduced to:
- Answer- none of the above
Bremsstrahlung (i.e., braking radiation) production of X-rays produces radiation that is
composed of: - Answer- A continuous spectrum of energies over some range
Collimators are used to: - Answer- Reduce the radiation beam spread
Image quality indicators (IQI's) provide information about the level of: - Answer-
Resolution and contrast sensitivity
In comparison with lower-voltage radiographs, high voltage radiographic images have: -
Answer- Less contrast sensitivity
Ionizing radiation can be used in industrial radiography because the health hazards: -
Answer- Are minimized through controls and procedures
Newton's Inverse Square Law is useful in radiography because it indicates how the
radiation intensity is affected by: - Answer- Distance from the source
, On a film radiograph, an area of high density in the test component will appear: -
Answer- Lighter than the surrounding area
The amount of geometric unsharpness in a radiograph is affected by: - Answer- the
source to film distance, the source to object distance, and the size of the source
The rate at which a radioactive isotope changes to a more stable atom is known as the:
- Answer- Isotope decay rate
Thin sheets of lead foil in contact with the film during exposure increase the film density
because: - Answer- Incident radiation liberates electrons which help to expose the film
The target of an X-ray tube is often made out of tungsten because: - Answer- It has a
high atomic mass which will result in more X-rays being generated due to atomic
particle interactions
Two of the more common industrial Gamma-ray sources are: - Answer- Cobalt-60 and
iridium-192
When flaws are in unknown locations, radiography is best suited for the detection of: -
Answer- Volumetric defects such as porosity
X-rays and Gamma rays: - Answer- Always travel in a straight line
X-rays and Gamma rays are often referred to as photons because: - Answer- The occur
as small packets of energy
X-rays and Gamma rays have significant penetrating power due to their: - Answer-
Short wavelength
X-rays and Gamma rays: - Answer- Differ only in their source
The thickness of any given material where 50% of the incident energy has been
attenuated is known as the: - Answer- Half-value layer
Unexposed X-ray film is comprised of a plastic, transparent base coated with an
emulsion containing radiation-sensitive particle known as: - Answer- Silver halide grains
Radiographic inspection should be used for crack detection only when: - Answer- The
orientation of the crack is known
X-rays and Gamma rays are a form of: - Answer- Electromagnetic radiation
Stationary lab or shop X-ray systems usually rely on what to limit exposure to the
radiation? - Answer- Shielding
ANSWERS
An X-ray film or IP having wide latitude (dynamic range) also has, by definition: -
Answer- low contrast
Thin sheets of lead foils in intimate contact with IP during exposure increase image
density because they: - Answer- emit electrons when exposed to X- and gamma
radiation which help darken the image
The adjustment of tube current in conventional X-ray tube circuits is made by: - Answer-
adjusting the filament heating current
The range of thickness over which densities are obtained that are satisfactory for
interpretation is a measure of the: - Answer- latitude (dynamic range) of a radiograph
Two isotropic sources of a given strength have two different specific activity values. The
source with the higher specific activity value will: - Answer- have a smaller physical size
than the source with a lower specific activity
After traveling through two half-value layers, the incident radiation has been reduced to:
- Answer- none of the above
Bremsstrahlung (i.e., braking radiation) production of X-rays produces radiation that is
composed of: - Answer- A continuous spectrum of energies over some range
Collimators are used to: - Answer- Reduce the radiation beam spread
Image quality indicators (IQI's) provide information about the level of: - Answer-
Resolution and contrast sensitivity
In comparison with lower-voltage radiographs, high voltage radiographic images have: -
Answer- Less contrast sensitivity
Ionizing radiation can be used in industrial radiography because the health hazards: -
Answer- Are minimized through controls and procedures
Newton's Inverse Square Law is useful in radiography because it indicates how the
radiation intensity is affected by: - Answer- Distance from the source
, On a film radiograph, an area of high density in the test component will appear: -
Answer- Lighter than the surrounding area
The amount of geometric unsharpness in a radiograph is affected by: - Answer- the
source to film distance, the source to object distance, and the size of the source
The rate at which a radioactive isotope changes to a more stable atom is known as the:
- Answer- Isotope decay rate
Thin sheets of lead foil in contact with the film during exposure increase the film density
because: - Answer- Incident radiation liberates electrons which help to expose the film
The target of an X-ray tube is often made out of tungsten because: - Answer- It has a
high atomic mass which will result in more X-rays being generated due to atomic
particle interactions
Two of the more common industrial Gamma-ray sources are: - Answer- Cobalt-60 and
iridium-192
When flaws are in unknown locations, radiography is best suited for the detection of: -
Answer- Volumetric defects such as porosity
X-rays and Gamma rays: - Answer- Always travel in a straight line
X-rays and Gamma rays are often referred to as photons because: - Answer- The occur
as small packets of energy
X-rays and Gamma rays have significant penetrating power due to their: - Answer-
Short wavelength
X-rays and Gamma rays: - Answer- Differ only in their source
The thickness of any given material where 50% of the incident energy has been
attenuated is known as the: - Answer- Half-value layer
Unexposed X-ray film is comprised of a plastic, transparent base coated with an
emulsion containing radiation-sensitive particle known as: - Answer- Silver halide grains
Radiographic inspection should be used for crack detection only when: - Answer- The
orientation of the crack is known
X-rays and Gamma rays are a form of: - Answer- Electromagnetic radiation
Stationary lab or shop X-ray systems usually rely on what to limit exposure to the
radiation? - Answer- Shielding
