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1

Ionizing radiation can be used in industrial radiography because the health hazards:

Have been eliminated with controls and proceduresAre minimized through controls and proceduresAre worth the riskAre being ignored

2

Unexposed X-ray film is comprised of a plastic, transparent base coated with an emulsion containing radiation-sensitive particle known as:

Metalic silver crystalsSilver halide grainsBoth A and BNeither A or B

3

Image quality indicators are usually placed:

Anywhere on the back side of the filmOn the front side of the film near the primary area of interestOn the front side of the test component in an area of similar thickness to the primary area of interestOn the back side of the test component in the area of interest

4

X-ray generators produce radiation through:

Bremsstrahlung processesK-shell emmission processesRadioactive decayBoth A and B

5

Radiographic inspection should be used for crack detection only when:

The crack is largeThe test componet is a castingThe test component is a weldmentThe orientation of the crack is known

6

When penetrating radiation is directed at a material, the radiation intensity decreases:

Decreases exponentially with increasing material thicknessIncrease linearly with increasing material thicknessDecrease linearly with increasing material thicknessNone of the above

7

Which of the following isnota strength of radiographic inspection?

It is not limited to material typeIt can be used to inspect assembled componentsIt can detect surface and subsurface featuresAccess to both side of the test sample is required

8

The number of X-ray or Gamma photons that are transmitted through a material depends on the:

Energy of the photonsThickness of the materialAtomic number of the materialAll of the above

9

The drive cable of a gamma ray exposure device (camera) allows the radiographer to:

Turn on and shut off the gamma rays from a safe distanceAdjust the position of the camera from a safe distanceMove the source in and out of the camera while maintaining a safe distanceNone of the above

10

Thin sheets of lead foil in contact with the film during exposure increase the film density because:

They act as a filter to harden the radiation beamThey reduce the amount of scatter radiationIncident radiation liberates electrons which help to expose the filmNone of the above

11

When using geometric magnefication to produce a radiograph, the penumbra will be reduced by:

A longer exposureA faster film speedA smaller source spot sizeMore X-ray energy

12

Collimators are used to:

Reduce the radiation beam spreadFilter the radiation beamIncrease film latitudeDecrease film latitude

13

Exposure to ionizing radiation can be limited:

With the use of shieldingBy increasing distance form the sourceBy limiting the time exposed to the radiaitonAll of the above

14

Computed tomography X-ray techniques allow the test component to be:

Viewed in various cross-sectional slicesViewed from different anglesAnalyzed for chemical compositionNone of the above

15

Higher energy radiation will have more:

SpeedIncident IntensityPenetrating powerBoth B and C

16

The target of an X-ray tube is often made out of tungsten becuase:

It has a high atomic mass which will result in more X-rays being generated due to atomic particle interactionsIt is an inexpensive material that is easy to machineIt have very high thermal conductivity which makes it easy to coolNone of the above

17

Who is given credit for the discovery of X-ray?

Henri BecquerelWilhelm RoentgenMarie CuriePierre Curie

18

When flaws are in unknown locations, radiography is best suited for the detection of:

Volumetric defects such as porosityTight linear defects such as cracksMaterial delaminationsThe flaw type does not matter

19

Which two types of radiation-matter interactions account for the majority of attenuation in typical industrial radiography?

Compton Scattering and photoelectric absorptionCompton Scattering and pair productionPair production and photoelectric absorptionNone of the above

20

In comparison with lower-voltage radiographs, high voltage radiographic images have:

Less contrast sensitivityGreater contrast sensitivityGreater amounts of scatter radiation relative to primary beam intensityLess latitude

21

Film contrast is determined by:

The type of film usedThe process by which the film was developedThe radiation energy usedBoth A and B

22

Stationary lab or shop X-ray systems usually rely on what to limit exposure to the radiation?

Distance controlsTime limitsShieldingAll of the above

23

The rate at which a radioactive isotope changes to a more stable atom is know as the:

Isotope decay rateHalf-lifeActivityAttenuation

24

Who is given credit for the discovery of radioactive materials?

Henri BecquerelWilhelm RoentgenMarie CuriePierre Curie

25

X-rays and Gamma rays:

Always travel in a straight lineCan be influenced by an electrical fieldCan be influenced by a magnetic fieldNone of the above

26

Undercut is the loss of resolution at a sharp, thickness transition area due to:

Scattering within the partBackscatterSidescatterScattering within the film

27

After traveling through two half-value layers, the incident radiation has been reduced to:

50%35%20%None of the above

28

X-rays and Gamma rays have significant penetrating power due to their:

Short wavelengthMedium wavelengthLong wavelengthWide range of wavelengths

29

Manmade sources of radioactive sources are produced by:

By splitting the nucleus of atoms in the source materialAdding electrons to the source materialIntroducing an extra neutron to the atoms of the source materialNone of the above

30

Two of the more common industrial Gamma-ray sources are:

Cobalt-60 and iridium-192Cobalt-60 and plutonium-240Plutonium-240 and uranium-222Iridium-192 and Lead-102

31

Which of the following doesnotaffect radiographic contrast?

Attenuation differences in the component being inspectedThe wavelength of the radiaiton usedThe amount of scattered radiationThe level of current used for the exposure

32

Lowering the energy of the radiation used to produce a radiograph will generally result in:

Less latitudeHigher contrast sensitivityA Longer exposure timeAll of the above

33

Image quality indicators (IQIs) provide information about the level of:

Resolution and contrast sensitivityResolution and film latitudeContrast sensitivity and latitudeContrast sensitivity only

34

The factor that indicates how much attenuation will take place per centimeter is known as the:

Mass attenuation coefficientLinear attenuation coefficientDecay rateAtomic number

35

Radiation beam filters are sometime used in X-ray radiography to:

Remove some of the low energy radiation to increase definitionTo remove some of the low energy radiation to increase contrast sensitivityRemove some of the low energy radiation to reduce definitionBoth A and B

36

The amount of geometric unsharpness in a radiograph is affected by:

The source to film distanceThe source to object distanceThe size of the sourceAll of the above

37

Attenuation of radiation is due to:

AbsorptionScatteringRadioactive decayBoth A and B

38

X-rays and Gamma rays:

Are both affected by radioactive decayAre both produced by a radioactive atomHave completely different propertiesDiffer only in their source

39

Newtons Inverse Square Law is useful in radiography because it indicates how the radiation intensity is affected by:

Radioactive decayDistance from the sourceThe size of the sourceNone of the above

40

X-rays and Gamma rays are a form of:

LightParticle radiationElectromagnetic radiationBoth B and C

41

A specific radioactive source will always produce gamma rays at the same:

IntensityActivityEnergy levelsNone of the above

42

X-rays and Gamma rays are often referred to as photons because:

They possess a chargeThey have massThey occur as small packets of energyNone of the above

43

The main advantage of real-time radiography over film is:

Higher image contrast sensitivityInspection can be performed more rapidlyHigher image definitionLower equipment costs

44

Bremsstrahlung production of X-rays produces radiation that is composed of:

A small number of very defined energiesA continuous spectrum of energies over some rangeRadiation of only one energyNone of the above

45

The thickness of any given material where 50% of the incident energy has been attenuated is known as the:

Half-value layerLinear attenuation coefficientDecay rateMass attenuation coefficient

46

X-rays and Gamma rays present a health risk because they are a form of ionizing radiation, which means that the radiation has enough energy to:

Vibrate water molecules and generate heatBreak chemical bondsBreak physical bondsNone of the above

47

On a film radiograph, an area of high density in the test component will appear:

Lighter than the surrounding areaDarker than the surrounding areaMore defined than the surrounding areaLess defined than the sorrounding area

48

There are four types of radiation-matter interactions that can contribute to the total attenuation. These are:

Compton scattering, pair production, photoelectric absorption, rayleigh scatteringCompton scattering, electron exchange, photoelectric absorption, rayleigh scattering

Electron exchange, pair production, photoelectric absorption, rayleigh scattering

None of the above

49

Radiographic contrast describe:

The sharpness of lines in a radiographThe differences in photographic density in a radiographThe average photographic density in a radiographThe difference in density between two different radiographs

50

A radiograph made with an exposure of 8 mAm produces a density of 1.8. The sensitometric curve shows a difference in relative exposure between a density of 1.8 and the target density of 2.5 is 4. What must the new exposure time be to produce a radiograph with a density of 2.5?

4 mAminutes2 mAminutes32 mAminutesNone of the above


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