RT Level III Study Questions with verified
answers
__(blank)__ and material thickness have the greatest impact on primary
beam energy reaching the film. Ans✓✓✓ Lead screen
1. __(blank)__ is a weld discontinuity caused by excessive current and
slow welding speed where molten metal drops to the opposite side of the
groove through the root while welding the sheet metal. Ans✓✓✓ Burn-
through
1. A basic difference between a radiograph and fluoroscopic image is:
Ans✓✓✓ The fluoroscopic image is positive whereas the radiographic
image is a negative transparency.
1. A Co60 source puts out 1.3 R/hr per Ci at 1 m. After 10.6 years the
output per Ci of a 70 Ci source will be __(blank)__. "Read what it is
asking for carefully" Ans✓✓✓ 1.3 R/Ci
1. A cold shut will appear in a radiograph as a __(blank)__ indication.
Ans✓✓✓ Curved or intermittent
1. A device utilized to absorb radiation from the center of radiation beam
and provide a more uniform distribution of intensity is a: Ans✓✓✓
Compensator
,1. A low energy isotope with a principal gamma peak at 52 KeV useful
for radiography of thin steel sections, light metals, plastics, and wood is:
Ans✓✓✓ Ytterbium-169
1. A penetrometer is used: Ans✓✓✓ To indicate the quality of the
radiographic technique
1. A radiograph is taken at a voltage of 500 kV. If the voltage is
increased to 600 kV while all other conditions remain the same:
Ans✓✓✓ There will be little change in the graininess of the radiograph
1. A series of well defined ruptures caused by high localized stresses
which develop as a casting cools would be identified as: Ans✓✓✓ Hot
Tears
1. A source of electrons is needed to bombard a target material in a
typical X-ray unit. This is accomplished by: Ans✓✓✓ Generating
thermal electrons at the cathode
1. A technique that is commonly used for large diameter pipes whereby
an entire circumferential weld can be radiographed in one exposure is
called: Ans✓✓✓ A panoramic exposure
1. According to the specification what type of source may be used?
Ans✓✓✓ Isotope
,1. All other design parameters being equal which of the following
operates at the highest applied voltage? Ans✓✓✓ Geiger Muller
detector
1. Alpha particles are __(blank)__ Ans✓✓✓ Helium nuclei
1. An assembly that contains a number of very minute components is
radiographed. In evaluating the radiograph, which one of the following
is most correct? Ans✓✓✓ use 3-5 X magnifier
1. An X-ray unit that generally produces both higher beam intensities
and higher energy radiographs show: Ans✓✓✓ Full-wave rectification
circuit
1. Areas having large dark spots appearing in the center of a weld due
loss of metal typically adjacent to large droplets protruding from the root
is referred to as __(blank)__ Ans✓✓✓ Burn-through
1. At energies above 100 KV when using lead screens, the primary film
response __(blank)__ Ans✓✓✓ Secondary electrons emitted from lead
1. At energies in excess of 100 KeV, using lead screens, the radiographic
film responds mainly to: Ans✓✓✓ Primary beam interaction of the
film.
, 1. Because it is normally produced as a water soluble compound, which
of the following is considered to have an additional radiological hazard
potential associated with it? Ans✓✓✓ Cesium-137
1. Characteristic radiation is known by a different term in X-ray
diffraction. Which of the following terms is it? Ans✓✓✓ Fluorescent
X-rays
1. During casting of a metal into a mold, cracking sometimes occurs due
to the shape and rigidity of the mold and stresses set up during the
cooling process which exceed the strength of the metal. These cracks or
defects appear in a radiograph as ragged dark lines and may be;
Ans✓✓✓ Hot tears
1. Films that remain between lead screens to long in high temperatures
and high humidity may: Ans✓✓✓ Become fogged
1. Fluoroscopic screens are typically coated with phosphors such as zinc
sulfide or zinc cadmium sulfide, which produce visible yellow-green
light with a wavelength of approximately: Ans✓✓✓ 5500 A
1. For large gamma sources, radiation intensity may not be proportional
to the source activity due to the effects of: Ans✓✓✓ Self-absorption
1. From strictly an energy standpoint, which one of the following
radioisotope sources would be the best choice for radiography of a steel
specimen 0.375 inch thick? Ans✓✓✓ Thulium-170
answers
__(blank)__ and material thickness have the greatest impact on primary
beam energy reaching the film. Ans✓✓✓ Lead screen
1. __(blank)__ is a weld discontinuity caused by excessive current and
slow welding speed where molten metal drops to the opposite side of the
groove through the root while welding the sheet metal. Ans✓✓✓ Burn-
through
1. A basic difference between a radiograph and fluoroscopic image is:
Ans✓✓✓ The fluoroscopic image is positive whereas the radiographic
image is a negative transparency.
1. A Co60 source puts out 1.3 R/hr per Ci at 1 m. After 10.6 years the
output per Ci of a 70 Ci source will be __(blank)__. "Read what it is
asking for carefully" Ans✓✓✓ 1.3 R/Ci
1. A cold shut will appear in a radiograph as a __(blank)__ indication.
Ans✓✓✓ Curved or intermittent
1. A device utilized to absorb radiation from the center of radiation beam
and provide a more uniform distribution of intensity is a: Ans✓✓✓
Compensator
,1. A low energy isotope with a principal gamma peak at 52 KeV useful
for radiography of thin steel sections, light metals, plastics, and wood is:
Ans✓✓✓ Ytterbium-169
1. A penetrometer is used: Ans✓✓✓ To indicate the quality of the
radiographic technique
1. A radiograph is taken at a voltage of 500 kV. If the voltage is
increased to 600 kV while all other conditions remain the same:
Ans✓✓✓ There will be little change in the graininess of the radiograph
1. A series of well defined ruptures caused by high localized stresses
which develop as a casting cools would be identified as: Ans✓✓✓ Hot
Tears
1. A source of electrons is needed to bombard a target material in a
typical X-ray unit. This is accomplished by: Ans✓✓✓ Generating
thermal electrons at the cathode
1. A technique that is commonly used for large diameter pipes whereby
an entire circumferential weld can be radiographed in one exposure is
called: Ans✓✓✓ A panoramic exposure
1. According to the specification what type of source may be used?
Ans✓✓✓ Isotope
,1. All other design parameters being equal which of the following
operates at the highest applied voltage? Ans✓✓✓ Geiger Muller
detector
1. Alpha particles are __(blank)__ Ans✓✓✓ Helium nuclei
1. An assembly that contains a number of very minute components is
radiographed. In evaluating the radiograph, which one of the following
is most correct? Ans✓✓✓ use 3-5 X magnifier
1. An X-ray unit that generally produces both higher beam intensities
and higher energy radiographs show: Ans✓✓✓ Full-wave rectification
circuit
1. Areas having large dark spots appearing in the center of a weld due
loss of metal typically adjacent to large droplets protruding from the root
is referred to as __(blank)__ Ans✓✓✓ Burn-through
1. At energies above 100 KV when using lead screens, the primary film
response __(blank)__ Ans✓✓✓ Secondary electrons emitted from lead
1. At energies in excess of 100 KeV, using lead screens, the radiographic
film responds mainly to: Ans✓✓✓ Primary beam interaction of the
film.
, 1. Because it is normally produced as a water soluble compound, which
of the following is considered to have an additional radiological hazard
potential associated with it? Ans✓✓✓ Cesium-137
1. Characteristic radiation is known by a different term in X-ray
diffraction. Which of the following terms is it? Ans✓✓✓ Fluorescent
X-rays
1. During casting of a metal into a mold, cracking sometimes occurs due
to the shape and rigidity of the mold and stresses set up during the
cooling process which exceed the strength of the metal. These cracks or
defects appear in a radiograph as ragged dark lines and may be;
Ans✓✓✓ Hot tears
1. Films that remain between lead screens to long in high temperatures
and high humidity may: Ans✓✓✓ Become fogged
1. Fluoroscopic screens are typically coated with phosphors such as zinc
sulfide or zinc cadmium sulfide, which produce visible yellow-green
light with a wavelength of approximately: Ans✓✓✓ 5500 A
1. For large gamma sources, radiation intensity may not be proportional
to the source activity due to the effects of: Ans✓✓✓ Self-absorption
1. From strictly an energy standpoint, which one of the following
radioisotope sources would be the best choice for radiography of a steel
specimen 0.375 inch thick? Ans✓✓✓ Thulium-170
