Term
| Increasing the kV setting on an X ray machine increases the: |
|
Definition
|
|
Term
| During the manufacturing of a casting, the purpose of a riser is: |
|
Definition
| To provide additional molten metal to allow for shrinkage during solidification |
|
|
Term
| An effective method of recognising a film artifact is: |
|
Definition
| Viewing film in reflected light from a viewer |
|
|
Term
A change in which of the following parameters would require a new X ray exposure
chart? |
|
Definition
|
|
Term
| Static marks on radiographic film are caused by: |
|
Definition
| Poor film handling technique |
|
|
Term
| Of the following radiographic sources, which emits the most penetrating radiation? |
|
Definition
|
|
Term
Which of the following techniques would probably reduce the amount of back
scattered radiation reaching the film during a radiographic exposure? |
|
Definition
| Backing the cassette with a sheet of lead |
|
|
Term
| Radiographic contrast is dependant on: |
|
Definition
| Density, Processing, Radiation energy |
|
|
Term
| A plot of film density versus log of relative exposure is called: |
|
Definition
| An H&D curve, A sensitometric curve, A characteristic curve |
|
|
Term
| The most common material used for targets in X ray tubes is: |
|
Definition
|
|
Term
A dark crescent shaped spot, clearly in the base metal adjacent to a weld would
probably be: |
|
Definition
|
|
Term
| Which of the following are potential sources of scattered radiation? |
|
Definition
| Test piece, Cassette, Floor |
|
|
Term
If the required exposure time for a 2220 GBq (60 curie) Ir-192 source is 2 minutes,
what exposure time would be required at 1110 GBq (30 curie) source: |
|
Definition
|
|
Term
| An advantage of a larger grain film is: |
|
Definition
|
|
Term
| How does radiation intensity change with increasing distance from the source? |
|
Definition
| Inversely with the square of distance |
|
|
Term
A weld discontinuity which consists of unmelted joint surfaces at the root, and which
may be caused by poor fit- up, is called: |
|
Definition
|
|
Term
| Mottling due to X ray diffraction can be identified by: |
|
Definition
Noting a slight change between two successive exposures with the test piece
rotated slightly about the beam axis |
|
|
Term
| Which of the following welding discontinuities would be considered the most serious? |
|
Definition
|
|
Term
A depression at the edge of a weld where the base metal has been melted during
welding is called: |
|
Definition
|
|
Term
| Which of the following would not be considered a film artifact? |
|
Definition
|
|
Term
Gamma ray or high voltage X ray radiography, using film without lead screens, is
likely to result in: |
|
Definition
|
|
Term
| Which of the following would be detrimental to radiographic image sharpness? |
|
Definition
| Small film focal distance |
|
|
Term
A change in which the following parameters would require a new X ray exposure
chart? |
|
Definition
|
|
Term
If the required exposure time for a 1850 GBq (50 curie) Ir-192 source is 4 minutes,
what exposure time would be required for 925 GBq (25 curie) source: |
|
Definition
|
|
Term
A radiograph is made using film X with an exposure of 10 mA-min. Film density
obtained in the area of interest is 1.0. If it is desired to achieve a density of 2.0 in the
area of interest, what exposure is required? (Log relative exposure = 1.1 for a density
of 1.0 and 1.62 for a density of 2.0) |
|
Definition
|
|
Term
| The least offensive of the following welding discontinuities would probably be: |
|
Definition
|
|
Term
| quantity calculated by the formula, 0.693/(decay constant), is called: |
|
Definition
|
|
Term
The density difference displayed from one area of a film radiograph to another is
called: |
|
Definition
|
|
Term
| The half-life of Co-60 is approximately |
|
Definition
|
|
Term
| Increasing the mA setting on an X ray machine: |
|
Definition
|
|
Term
| Which of the following would be considered a film artifact? |
|
Definition
|
|
Term
| Which of the following would be detrimental to radiographic image sharpness? |
|
Definition
| Large film focal distance |
|
|
Term
| The half-life of Ir-192 is approximately: |
|
Definition
|
|
Term
A dark crescent shaped mark in the centre of a weld bead radiographic image would
probably be: |
|
Definition
|
|
Term
A photon-nuclear interaction in which energy is converted into sub-atomic particles is
called: |
|
Definition
|
|
Term
An interaction in which radiation is produced by the rapid deceleration of an electron
is called: |
|
Definition
|
|
Term
| The gamma factor of Tm-170 is: |
|
Definition
| 0.0062 R·h-1·Ci-1 at one metre |
|
|
Term
An exposed radiographic film which transmits 1% of the light incident on it has what
density: |
|
Definition
|
|
Term
If the radiation intensity is 5 Gy/h (500 R/h) at a distance of 152.4 cm (5 feet) from a
source, what is the intensity at 1524 cm (50 feet)? |
|
Definition
|
|
Term
| The average energy of a Cs-137 source is approximately: |
|
Definition
|
|
Term
Which of the following is an advantage of X ray over gamma ray sources for
radiography? |
|
Definition
| Variable radiation energy |
|
|
Term
| The basic purpose of a penetrameter is to: |
|
Definition
| Indicate quality of the radiographic technique |
|
|
Term
When a casting is being non destructively examined for critical service, and the
possibility of cracks exists, which of the following techniques would be best? |
|
Definition
| Magnetic Particle or Liquid Penetrant testing |
|
|
Term
Which of the following is an advantage of X ray over gamma ray sources for
radiography? |
|
Definition
| Safety, Variable radiation intensity, Variable radiation energy |
|
|
Term
| The average energy of a T3-170 source is approximately: |
|
Definition
|
|
Term
| The gamma factor of Co-60 is: |
|
Definition
| 1.37 R·h-1·Ci-1 at one metre |
|
|
Term
| The intensifying effect of lead screens is mainly caused by: |
|
Definition
|
|
Term
| Which of the following expressions correctly determines radiographic density? |
|
Definition
|
|
Term
The most significant difference in two X ray beams produced at different kV settings
is: |
|
Definition
|
|
Term
| Most significant difference in two X ray beams produced at different mA settings is: |
|
Definition
|
|
Term
| Which of the following would be considered a film artifact? |
|
Definition
|
|
Term
Natural discontinuities comparable in size to the penetrameter holes shown on a
radiograph may not be detected because: |
|
Definition
Natural discontinuities do not necessarily have as sharp edges as the
penetrameter holes |
|
|
Term
If the radiation intensity is 1 Gy/h (100 R/h) at a distance of 152.4 cm (5 feet) from a
source, what is the intensity at 610 cm (20 feet)? |
|
Definition
|
|
Term
| Fluorescent screens are seldom used in industrial radiography because: |
|
Definition
| Poor definition and screen mottle can result |
|
|
Term
| Calculate geometric unsharpness for the following conditions: Source size = 2 mm × 2 mm; SFD = 700 mm; test piece thickness = 25 mm |
|
Definition
|
|
Term
| The gamma factor of Ir-192 is: |
|
Definition
| 0.59 R·h-1·Ci-1 at one metre |
|
|
Term
| A test piece with large differences in thickness would have: |
|
Definition
|
|
Term
| A quantity expressed by the formula, 0.693/(absorption co-efficient) is called: |
|
Definition
|
|
Term
Which of the following techniques would probably reduce the amount of scattered
radiation reaching the film during a radiographic exposure? |
|
Definition
| Using a filtered X ray beam |
|
|
Term
| A radiographic indication in a weld, characterised by two parallel dark lines in the film image, would probably be caused by: |
|
Definition
|
|
Term
| To produce the sharpest image, which of the following should be true? |
|
Definition
| The radiographic source should be small |
|
|
Term
| ‘Undercut’ or ‘burned out’ edges of the test piece film image are caused by: |
|
Definition
|
|
Term
Which of the following is an advantage of gamma ray over X ray sources for
radiography? |
|
Definition
| Portability, No external power supply needed, Ruggedness |
|
|
Term
| The intensifying effects of fluorescent screens are caused by: |
|
Definition
|
|
Term
If the required X ray exposure time for a 225 kV, 5 mA exposure is 3 minutes,
approximately what exposure time would be required at 10 mA? |
|
Definition
|
|
Term
| The half-life of Cs-137 is approximately: |
|
Definition
|
|
Term
| Unacceptable radiographic film quality would be indicated by: |
|
Definition
| Artifacts of known origin in the film's area of interest, Use of a smaller penetrameter than required, H & D density less than 2.0 |
|
|
Term
| Which of the following welding discontinuities would be most difficult to image radiographically: |
|
Definition
|
|
Term
| The most important factor in limiting radiation exposure is: |
|
Definition
| Time, Distance, Shielding |
|
|
Term
| The threshold energy below which pair production cannot occur is approximately: |
|
Definition
|
|
Term
A photon-electron interaction in which a photon gives up all its energy to an electron
is called: |
|
Definition
|
|
Term
| An acceptable quality radiograph should include: |
|
Definition
| Proper identification, Correct penetrameter and visible holes, Location markers |
|
|
Term
For gamma ray sources, radiographic intensity is proportional to source activity in
gigabecquerels or curies for: |
|
Definition
|
|
Term
| Poor contact between lead screens and film is likely to cause: |
|
Definition
| An indistinct or ‘fuzzy’ image |
|
|
Term
| Which of the following conditions might cause mottling of a radiographic film? |
|
Definition
| Back scatter from aged fluorescent screens |
|
|
Term
A photon-electron interaction in which a photon gives up a portion of its energy to an
electron is called: |
|
Definition
|
|
Term
If the radiation intensity is 5.9 Gy/h (590 R/h) at a distance of 30.5 cm (1 foot) from a
source, how far is it to the point where the radiation intensity is 0.02 Gy/h (2 R/h)? |
|
Definition
|
|
Term
If the radiation intensity is 5 Gy/h (500 R/h) at a distance of 152.4 cm (5 feet) from a
source, how far is it to the point where the radiation intensity is 0.05 Gy/h (5 R/h)? |
|
Definition
|
|
Term
Which of the following techniques would probably reduce the amount of scattered
radiation reaching the film during a radiographic exposure? |
|
Definition
|
|
Term
| The lights in a high intensity viewer are typically: |
|
Definition
|
|
Term
| The gamma factor of Cs-137 is: |
|
Definition
| 0.38 R·h-1·Ci-1 at one metre |
|
|
Term
If the required X ray exposure time for a 150 kV, 5 mA exposure is 2 minutes,
approximately what exposure time would be required at 10 mA? |
|
Definition
|
|
Term
| A thin, jagged, dark line inside the weld image on a radiographic film is probably: |
|
Definition
|
|
Term
A straight, dark line in the centre of a weld bead image on film would be suspected of
being: |
|
Definition
|
|
Term
‘Undercut’ or ‘burned out’ edges of the test piece in film image can usually be reduced
by: |
|
Definition
|
|
Term
| Which of the following would be detrimental to radiographic image sharpness? |
|
Definition
| Large object to film distance |
|
|
