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Question 1

1. In the SI System, the distinction between upper and lower case letters is meaningful and should be observed. For example, the meanings of the prefix the M (mega) differ by how many orders of magnitude?
   a. 3
   b. 6
   c. 9
   d. 12

Answer 1

c. 9

Question 2

3. If one-eighth of a sample of a radioisotope remains after 24 years, what is the half-life of the radioisotope?
   a. 3 years
   b. 4 years
   c. 6 years
   d. 8 years
   AÑOS VIDA MEDIA
   6 1/2
   12 1/4
   24 1/8

Answer 2

c. 6 years

Question 3

4. A positively charged particle with a mass equal to the electron is the:
   a. proton,
   b. positron.
   c. meson.
   d. deuteron.

Answer 3

b. positron.

Question 4

5. The number of protons in the nucleus is called the:
   a. atomic mass.
   b. atomic weight.
   c. atomic number.
   d. relative atomic mass

Answer 4

c. atomic number

Question 5

6. Which of the following is not one of the five primary modes by which atoms disintegrate?
   a. Emission of an alpha particle.
   b. Emission of a beta particle,
   c. Quantum scintillation.
   d. Spontaneous fission.

Answer 5

c. Quantum scintillation.

Question 6

6. Emission of an alpha particle decreases the mass Of the nucleus by _ and the atomic number by
   a. 4.4
   b. 4.2
   c. 2.2
   d. 2.4

Answer 6

b. 4.2

Question 7

8. After 4 half-lives, what percentage of a radioisotopo life remains?
   a. 25%
   b. 12.5%
   c. 6,25%
   d. 3,12%
   AÑOS VIDA MEDIA PORCENTAJE %
   1 1/2 50
   2 1/4 25
   3 1/8 12.5
   4 1/8 6.25

Answer 7

c. 6,25%

Question 8

9. The effective reduction in energy caused by the absorption of a photon, and the release of a lower-energy photon, is called :
   a. the photoelectric effect.
   b. compton scattering.
   c. pair production.
   d. rayleigh scattering.

Answer 8

b. compton scattering

Question 9

10. Beta particles are identical to high-speed electrons with the following exception that:
    a. they may be either positively or negatively charged.
    b. they have twice the rest mass.
    c. they have opposite spin and magnetic moment.
    d. they have twice the compton wavelength.

Answer 9

a. they may be either positively or negatively charged.

Question 10

11. Which of the following is not one of the three major photon attenuation processes?
    a. Compton scattering.
    b. Photoelectric effect.
    c. pair production.
    d. Electron capture.

Answer 10

b. Photoelectric effect.

Question 11

12. In the SI system, the unit of energy is the:
    a. joule.
    b. Pascal.
    c. newton.
    d. watt.

Answer 11

a. joule.

Question 12

13. An alpha particle is:
    a. one particle in the class of particles called leptons. b. identical to a helium nucleus.
    c. a type of quark
    d. very small compared to other particles.

Answer 12

b. identical to a helium nucleus.

Question 13

14. A semilogarithmic plot of the percent of radioactive material remaining versus time results in:
    a. an ellipse.
    b. a hyperbolic curve.
    c. a quadratic curve.
    d. a straight line.

Answer 13

d. a straight line.

Question 14

15. The creation of a positron and an electron from the interaction of a photon with an energy of at least 1.02 MeV and a strong electric field, such as that surrounding an atomic nucleus, is called:
    a. the photoelectric effect.
    b. compton scattering.
    c. pair production.
    d. rayleigh scattering.

Answer 14

c. pair production.

Question 15

16. Emission of a beta particle changes the Of the nucleus by____and the atomic number by____
    a. 0, 1
    b. +1, 1
    c. -1, 1
    d. -1, 0

Answer 15

a. 0, 1

Question 16

17. ANSI, ASNT, ASTM, IEEE, ISO, and NIST all support the replacement of the older imperial units of radiation measurement with Sl units. The new units that replace the curie, roentgen, rad, and rem are:
    a. joule, newtons per kilogram, gray, and sievert.
    b. becquerel, newton-meter, coulomb, and sievert.
    c. joule, becquerel, coulomb, and sievert.
    d. becquerel, coulomb per kilogram. gray, and sievert.

Answer 16

d. becquerel, coulomb per kilogram. gray, and sievert.

Question 17

18. What is meant by the dual nature Of the photon?
    a. It has both charge and mass.
    b. It behaves as both a particle and a wave.
    c. It has both spin and charge.
    d. It can produce both ionization and decay.

Answer 17

b. It behaves as both a particle and a wave.

Question 18

19. The atomic mass is:
    a. the number of protons and neutrons in the nucleus.
    b. the cumulative weight of nucleons and electrons in an atom.
    c. the rest mass of all particles that an atom consists of.
    d. the cumulative weight of electrons in an atom.

Answer 18

a. the number of protons and neutrons in the nucleus.

Question 19

20. The liberation of electrons from a substance exposed to electromagnetic radiation is called;
    a. the photoelectric effect.
    b. compton scattering.
    c. pair production.
    d. rayleigh scattering.

Answer 19

a. the photoelectric effect.

Question 20

21. Given the linear attenuation coefficient for 0.6 MeV photons passing through lead is 1.36/cm, what is the half-value layer thickness?
    a. 0,1 cm
    b. 0,1 pulg.
    c. 0,2 pulgadas
    d. 1 cm

Answer 20

c. 0,2 pulgadas

Question 21

1. The probability of absorption of any particular radiation type and energy by a specific element is referred to as the:
   a. attenuation.
   b. buildup factor.
   c. cross section.
   d. atomic coefficient.

Answer 21

c. cross section.

Question 22

2. Which of the following is not a form for expressing attenuation coefficients?
   a. Rayleigh.
   b. Atomic.
   c. Linear.
   d. Mass.

Answer 22

a. Rayleigh

Question 23

3. A material with a 250 mm (9.83 in.) TVI. has HVL an
   a. 24.96 mm (0.983 in.)
   b. 75.26 mm (2.96 in.)
   c. 82.29 mm (3.24 in.)
   d. 124.96 mm (4.92 in.)

Answer 23

b. 75.26 mm (2.96 in.)

Question 24

4. If a specific material had a linear attenuation coefficient of 0,2 cm-1, what would the HVL be in that material?
   a. 14.2 mm
   b. 34.7 mm
   c. 36.6 mm
   d. 87.6 mm

Answer 24

b. 34.7 mm

Question 25

5. If the intensity of a radiation source was initially 25,8 mC/kg per hour (100 R per hour) and it was desired to reduce this intensity to 2,58 mC/kg per hour (10 R per hour), what thickness of shield would be required? Assume that the linear attenuation coefficient for the specific energy is 0,9 cm-1. a. 02.0 mm b. 25.6 mm c. 82.8 mm d. 96.0 mm

Answer 25

b. 25.6 mm

Question 26

6. What would be the facility workload for a busy exposure cell with the following average techniques: 110 exposures per week at 10 mA*min; 500 exposures per week at 22 mA*min; 1150 exposures per week at 5 mA*min. a. 7850 mA*min per week. b. 17850 mA*min per week c, 34600 mA*min per week, d. 2550 mA*min per day.

Answer 26

b. 17850 mA*min per week

Question 27

7. Un factor de ocupación comúnmente utilizado para fines de diseño de áreas de aceras no controladas es: a. 1/4 b. 1/5 c. 1/16 d. 1

Answer 27

c. 1/16

Question 28

1. X-rays may be produced when_____high-speed are stopped by a high atomic number target. a. electrons b. protons c. hydrogen ions d. helium ions

Answer 28

a. electrons

Question 29

2. Neutron activation produces radioisotopes by. a. excitation of the nuclei of the target atoms by neutrons. b. loss of electrons, caused by neutron bombardment, from the target atoms. c. capture of a neutron by the target atoms. d. loss of a neutron by the target atoms.

Answer 29

c. capture of a neutron by the target atoms.

Question 30

3. Which of the following may be produced by neutron activation? a. Co-60 b. Cs-137 c. Ra-116 d. Ir-191

Answer 30

a. Co-60

Question 31

4. Which of the following may be produced as a product of fission? a. Co-60 b. Cs-137 c. Ir-192 d. Ra-116

Answer 31

b. Cs-137

Question 32

5. Radiographic Sources are encapsulated to: a. improve the gamma ray output. b. harden the radiation beam. c. increase the cost of the sources. d. prevent loss of the radioactive material.

Answer 32

d. prevent loss of the radioactive material.

Question 33

6. An acceptable modern radiographic exposure device may be a radiographic source: a. suspended from a pole by a string. b. on a cylinder of shielding material rotating in a larger cylinder of shielding material. c. held by a flexible cable. d. that may be removed from a shield by long tongs or pliers so that it can be placed for exposure.

Answer 33

b. on a cylinder of shielding material rotating in a larger cylinder of shielding material.

Question 34

7. Un dispositivo de exposición radiográfica moderno aceptable como material de protección. a. plomo b. uranio empobrecido c. acero d. tungsteno

Answer 34

b. uranio empobrecido

Question 35

8. In the doughnut-shaped tube of a betatron, electrons are accelerated to high speeds by: a. RF power phasing. b. uniform voltaje distribution c. magnetic induction. d. an insulated charging belt.

Answer 35

c. magnetic induction.

Question 36

9. Electrostatic generators (van de graaff) for radiography operate in the range of: a. 1 a 3,5 Mev. b. 5 a 10 MeV. c. 10 a 15 MeV. d. 15 a 25 MeV.

Answer 36

a. 1 a 3,5 Mev.

Question 37

10. The high-frequency waves of energy generated by the magnetron in a linear accelerator are in which band of the frequency spectrum? a. Banda-L. b. Banda-M c. Banda-K. d. Banda-S

Answer 37

d. Banda-S

Question 38

11. The efficiency of target material in the production of X-rays is______ to its atomic number. a. equal b. proportional c. unrelated d. more dependent On target than shape

Answer 38

b. proportional

Question 39

1. Which one of the following radioisotopes is not naturally occurring? a. Cs-137 b. Ra-226 c. K-40 d. C-14

Answer 39

a. Cs-137

Question 40

2. Which of the following human cell categories is the most sensitive to radiation exposure? a. Granulocytes. b. Basal cells. c. Bile duct cells. d. Lymphocytes.

Answer 40

d. Lymphocytes.

Question 41

3. If an X-radiation exposure of 1.5 mC/kg (5.8 R) is received by an individual during an incident, what is the individual's dose equivalent? a. 0.058 Sv (5.8 rem) b. 0.029 Gy (2.9 rad) c. 0.232 Sv (23.2 rem) d. 0.116 Sv (11.6 rem)

Answer 41

a. 0.058 Sv (5.8 rem)

Question 42

4. The imperial unit of radiation, the curie, is 3,7 x 10-10 disintegrations per second, How many disintegrations per second is the Sl unit, the becquerel? a. 1000 b. 100 c. 10 d. 1

Answer 42

d. 1

Question 43

5. When using film as the method for neutron personnel monitoring, what filter material is used to produce an reaction, which will increase the film density after neutron exposure? a. Tin. b. Polyethylene terephthalate. c. Cadmium. d. Brass.

Answer 43

c. Cadmium.

Question 44

6. Specific areas of the Code of Federal Regulations used frequently by radiography licensees arc: a. 10CFR20. b. 10CFR40. c. 10CFR50. d. 10CFR70

Answer 44

a. 10CFR20.

Question 45

7. In accordance with Department of Transportation regulations, radioactive materials are classified into which two categories? a. Hazardous and nonhazardous. b. Normal and special. c. Penetrati and nonpenetrating_ d. Type I and Type II

Answer 45

b. Normal and special.

Question 46

8. If an exposure of approximately 3 Sv (300 rem) of gamma radiation was received to the whole body of an individual, which one of the following would not be likely? a. White cell count decrease. b. Vomiting. c. Diarrhea. d. Death.

Answer 46

d. Death.

Question 47

9, The critical difference between the operation of detectors in the ionization, geiger-muller, and proportional region is the; a. pulse duration. b. voltage applied to the center electrode. c. specific ionization of the chamber gas. d. amperage of the chamber circuit.

Answer 47

b. voltage applied to the center electrode.

Question 48

10. All other design parameters being equal, which of the following operates at the highest applied voltage? a. Geiger-muller detector. b. Ionization chamber detector. c. Proportional detector, d. Photomultiplier tube.

Answer 48

a. Geiger-muller detector.

Question 49

11. The minimum amount of energy required to produce an ion pair in air is approximately: a. 100 eV b. 68 keV c. 0.510 MeV d. 34 eV

Answer 49

d. 34 eV

Question 50

12. Survey instruments used to monitor radiography operations should have a range of at least: a. 0,258 a 516 μC/kg por h (1 a 2000 mR/h). b. 0,516 a 2580 μC/kg por h (2 a 10 000 mR/h). c. 0,516 a 516 μC/kg por h (2 a 2000 mR/h). d. 0,516 a 258 μC/kg por h (2 a 1000 mR/h).

Answer 50

d. 0,516 a 258 μC/kg por h (2 a 1000 mR/h).

Question 51

15. The detection efficiencies of scintillation detectors over gas ionization chambers for photons is approximately: a. 10a6 veces mayor. b. 10a3 veces mayor. c. 10a4 veces mayor. d. 10a9 veces mayor.

Answer 51

a. 10a6 veces mayor.

Question 52

16. Which of the following survey instrument types is usually considered least susceptible to moisture and physical shock? a. proportional counter instruments. b. Ionintion chamber instruments. c. Geiger-mûller tube instruments. d. Bonner sphere instruments.

Answer 52

c. Geiger-mûller tube instruments.

Question 53

3. In general, when using the composite film viewing technique, each film should have a minimum density a. 1.3 b. 1.5 c. 1.8 d. 2.0

Answer 53

a. 1.3

Question 54

5. The graphic presentation that depicts the relationship between exposure and the resulting photographic density for a particular film type is commonly referred to as a; a. linear Curve. b. characteristic curve. c. spectral curve. d. logarithmic curve,

Answer 54

b. characteristic curve.

Question 55

1. Una imagen de 16 bits tiene un rango de valores de gris de hasta: a. 256 b. 1024 c. 65536 d. 16777216

Answer 55

c. 65536

Question 56

2. Digital radiography does not include: a. computed radiography. b. direct conversion. c. indirect conversion. d. film.

Answer 56

d. film.

Question 57

3. Smaller pixel sire results in: a. higher maximum achievable spatial resolution. b. lower maximum achievable spatial resolution. c. higher maximum achievable spatial resolution. d. lower minimum achievable spatial resolution.

Answer 57

a. higher maximum achievable spatial resolution.

Question 58

4. For optimum performance, image review should be performed: a. in a normally Iighted work area. b. in subdued lighting. c. in a darkroom. d. in a brightly lit room.

Answer 58

b. in subdued lighting.

Question 59

5. Monitor performance needs to be checked: a. when a system is purchased or set up. b. every half hour. c. regularly for brightness and ability to distinguish line pairs in an SMTP test pattern. d. never.

Answer 59

c. regularly for brightness and ability to distinguish line pairs in an SMTP test pattern.

Question 60

6. Digital radiography: a. includes computed radiography and computed tomography. b. includes computed radiography but not computed tomography. c. includes computed tomography but not computed radiography. d. is completely different from both computed tomography and computed radiography.

Answer 60

a. includes computed radiography and computed tomography.

Question 61

7. Lossy compression: a. reproduces an image or file exactly, keeping all Of the information intact. b. loses some of the image or file data, and does not keep all of the information intact. c. recreates a compressed file as an identical match to its original form. d. makes file sizes larger.

Answer 61

b. loses some of the image or file data, and does not keep all of the information intact.

Question 62

8. To make use of a larger portion of the display if the operator wants to focus on a subset of the image, you would use: a. optical magnification, b. geometric magnification. c. a different type of detector. d. a magnifying glass.

Answer 62

a. optical magnification,

Question 63

9. Greater bit depth: a. gives a smaller range of tones (grayscale) in an Image. b. gives a higher range of tones (grayscale) in an image, c. gives the same number of tones (grayscale) in an Image. d. has no impact on grayscale in an image.

Answer 63

b. gives a higher range of tones (grayscale) in an image,

Question 64

10. A pixel is: a. the smallest addressable element in a display device. b. the average addressable element in a display device. c. the largest addressable element in a display device. d. a three-dimensional representation of data.

Answer 64

a. the smallest addressable element in a display device.

Question 65

11. JPEG images are most commonly used for image review and acceptance of product because: a. compression makes the file sizes smaller and easier to manage. b. the image quality is improved. c. JPEG allows for more bit depth than other file d. JPEG images are not used for image review and acceptance.

Answer 65

d. JPEG images are not used for image review and acceptance.

Question 66

1. Storage phosphor readouts are performed by: a. a charge coupled device. b. an amorphous silicon detector, c. an amorphous selenium detector. d. a laser and photomultiplier tube.

Answer 66

d. a laser and photomultiplier tube.

Question 67

2. A direct conversion detector functions by: a. converting the radiation directly into a digital signal. b. storing the energy from absorbed radiation for later conversion to a digital signal. c. use of a scanning laser. d. measuring light transmitted through film.

Answer 67

a. converting the radiation directly into a digital signal.

Question 68

3. Which of the following are examples of types of digital detector arrays? a. Amorphous silicon, charge coupled device, storage phosphor plate. b. Amorphous silicon, charge coupled device, linear detector array. c. Amorphous silicon, storage phosphor plate. linear detector array. d. Charge coupled device, storage phosphor plate, linear detector array.

Answer 68

b. Amorphous silicon, charge coupled device, linear detector array.

Question 69

4. Film digitization works by. a. using a storage phosphor to store the image for later retrieval by a laser readout device. b. measuring the light transmitted through a sheet of film. c. takinga picture of the film with a CCD camera. d. radiographing the film in front of a digital detector.

Answer 69

b. measuring the light transmitted through a sheet of film.

Question 70

5. Flat panel detectors have an expected life span that is dependent upon: a. the amount of calendar time it is installed in an X-ray system. b. the total dose, dose rate and radiation energy. c. the care taken to install the detector into a fixture. d. how carefully the operator turns the equipment on and off.

Answer 70

b. the total dose, dose rate and radiation energy.

Question 71

6. The main advantage of linear detector arrays is that: a. the scatter field is reduced. b. larger images can be taken without moving the detector or part. c. the indirect conversion is more efficient. d. the larger area of the detector allows inspection of larger items with single, short exposures.

Answer 71

a. the scatter field is reduced.

Question 72

7. One advantage of storage phosphor imaging plates is: a. they have an extremely wide dynamic range. b. they require more radiation to perform exposures. c. they never wear out from use or handling. d. the direct cable connection to the computer eliminates the need to enter the exposure area.

Answer 72

a. they have an extremely wide dynamic range.

Question 73

8. The performance of digital X-ray detectors: a. is dependent on the efficiency of each step of the converslon process, b. is always good, otherwise the vendor would not sell them. c. is never good, and offers no new capabilities. Radiographers should stick with film for all applications. d. varies dependent on the time of day and year.

Answer 73

a. is dependent on the efficiency of each step of the converslon process,

Question 74

9. One of the big differences between film and digital radiography is: a. film has more variation in detection ability options. b. digital is more simple. c. digital has a wider range of implementation concepts. d. film allows for more image processing.

Answer 74

c. digital has a wider range of implementation concepts.

Question 75

1. Digital radiography: a. allows for image processing capabilities not possible with film. b. does not allow for the same image processing capabilities as film. c. requires attention to be paid only to the image acquisition. d. requires attention to be paid only to the image review.

Answer 75

a. allows for image processing capabilities not possible with film.

Question 76

2. An image With an excellent spatial frequency response: a. will always be acceptable. b. will never be acceptable. c. might be acceptable depending on other parameters. d. does not require a good SNR

Answer 76

c. might be acceptable depending on other parameters.

Question 77

3. Line profiles are most Often used to: a. compare one line to another. b. increase the signal-to-noise ratio. c. increase the contrast-to-noise d. analyze an edge.

Answer 77

d. analyze an edge.

Question 78

4, Measurements made on digital images; a. are always better than measurements made on the film. b. never better than measurements made on the film. c. are the same as With film. d. require the software measurement tool to be calibrated.

Answer 78

d. require the software measurement tool to be calibrated.

Question 79

5. Adjusting the grayscale displayed in an image is done a. window leveling. b. SNR verification. c. histogram equalization. d. adjusting monitor brightness.

Answer 79

a. window leveling.

Question 80

6. pseudo color is best used to: a. improve the SNR. b. make a known feature stand out more clearly. c. make the image easier to interpret. d. convert color images to grayscale.

Answer 80

b. make a known feature stand out more clearly.

Question 81

7. A high-pass filter: a. sharpens an image but enhances noise. b. sharpens an image and reduces noise. c. only sharpens an image. d. only reduces noise in an image.

Answer 81

a. sharpens an image but enhances noise.

Question 82

8. A median filter: a. sharpens an image. b. an image, c. increases noise. d. flattens the image.

Answer 82

d. flattens the image.

Question 83

9. umbral (Threshholding) a. produces a binary image. b. increases the SNR. c. sharpens an image. d. eliminates all noise.

Answer 83

a. produces a binary image.

Question 84

1. Various radiographic techniques require special consideration to reduce scatter radiation reaching the film. Which of the following does not constitute a good masking material? a. Lead acetate/lead nitrate in water. b. Steel shot. c. Aluminum. d. Barium clay

Answer 84

c. Aluminum

Question 85

2. When radiographing a steel specimen 19 mm (0.75 in.) thick with 275 kv peak X-rays, the use ofa copper filter that is_____of the specimen thickness is recommended (if more latitude is necessary). a. 20% b. 10% c. 4% d. 15%

Answer 85

a. 20%

Question 86

3. A multi-film technique may be necessary when radiographic inspection is to be performed on a: a. butt weld between 5 cm (2 in.) thick plates. b. consumable insert weld on small-diameter pipe. c. long seam weld on a storage tank. d. large vessel nozzle weld.

Answer 86

d. large vessel nozzle weld.

Question 87

4. One of the major benefits Of the use of a radiographic enlargement technique is that it: a. increases the focal spot size. b. reduces scatter radiation. c. decreases geometric unsharpness. d. decreases exposure time.

Answer 87

b. reduces scatter radiation.

Question 88

5. In Stereo radiography, the shift of the X-ray tube for the required second exposure is based on the: a. thickness of the part. b. type of indication being evaluated c. type of prisms used in the stereoscope. d. normal interpupillary distance.

Answer 88

d. normal interpupillary distance.

Question 89

6. The triangulation techniques to determine the depth of a discontinuity is based on the relationship: a. source-to-film b. similar triangle. c. markers-to-film. d. shift-to-time

Answer 89

b. similar triangle.

Question 90

7. When using the rigid formula for triangulation, it is important to remember that the discontinuity height and image shift are: a. linear. b. proportional. c. nonlinear. d. critical.

Answer 90

c. nonlinear.

Question 91

8. The relative position Of a discontinuity between the outside and inside surfaces can be obtained by linear interpolation when using the: a. double-marker formula. b. step technique, c. single-marker formula. d. rigid formula.

Answer 91

a. double-marker formula.

Question 92

9. The technique for in-motion radiography is essentially the same as conventional techniques except the exposure time is based on: a. source-to-film distance, b. DIT ratio. c. speed of travel. d. geometric unsharpness considerations.

Answer 92

c. speed of travel.

Question 93

10. There are currently three in-motion radiography techniques used in industry. Which of the following listed techniques is not an in-motion radiographic technique? a. Linear motion. b. Rotary motion. c. Stereographic motion. d. Synchronous radiograph.

Answer 93

c. Stereographic motion.

Question 94

11. A higher percentage loss of usable radiation is expected during in-motion radiographic techniques as the result of: a. collimation. b. filtration. c. speed of travel. d. absorption,

Answer 94

a. collimation.

Question 95

12. X-ray diffraction and the resultant patterns recorded on the inspection medium are of primary concern when radiographing: a. thick sections of steel specimens. b. aluminum specimens. c. bimetallic weld samples. d. coarse grained metallic specimens.

Answer 95

d. coarse grained metallic specimens.

Question 96

13. If the panoramic technique of radiography is selected, one of the most important factors to be considered is a. material composition. b. thickness uniformity. c. film type- d. IQI requirements.

Answer 96

b. thickness uniformity.

Question 97

14. In high-energy radiographic applications, Screens vary depending on the energy used. When using an 8 MeV linear accelerator, which of the following thicknesses would be the most appropriate front screen thickness? a. 0.76 mm (0.030 in.) pb b. 3.18 mm (0. 125 in.) pb c. 0.25 mm (0.010 in.) Pb d. 6.4 mm (0250 in.) Al

Answer 97

a. 0.76 mm (0.030 in.) pb

Question 98

1. A computed tomography (CT) system consists of: a. an X-ray tube and detector. b. a radiation source and film Cassette. c. a radiation source, detector, mechanical assembly, and computer. d. a computer, X -ray tube, and detector.

Answer 98

c. a radiation source, detector, mechanical assembly, and computer.

Question 99

2. CT differs from conventional radiographic imaging: a. because it builds on medical technology, making it is less expensive. b. by the type of radiation source used. c. because of the detectors used. d. because the features are not superimposed.

Answer 99

d. because the features are not superimposed.

Question 100

3. Ray interactions for CT_____ conventional radiography. a. different from b. the same as c. perpendicular to d. stronger than

Answer 100

b. the same as

Question 101

4. A set of line integrals is referred_______to______ as can be referred to as a______ a. views, view, projection or profile b. samples. view, data sample c. data, data sample, view d. projection, data sample, view

Answer 101

a. views, view, projection or profile

Question 102

5. _______can be thought of as reversing the data collection process_____is the most common form of _____ a. Projections, Reconstruction, backprojection b. Reconstruction, Projection, backprojection c. Backprojection, Reconstruction. convolution-backprojection d. Backprojection, Convolution-backprojection, reconstruction

Answer 102

d. Backprojection, Convolution-backprojection, reconstruction

Question 103

6. A finite number and width of X-ray beams causes the blurring of a feature. This blurring function is called the: a. modulation transfer function. b. point-spread function (PSF). c. modulus of fourier transform. d. reproduction of spatial frequencies.

Answer 103

b. point-spread function (PSF).

Question 104

7. The ability to sense that two features are distinct refers to: a. spatial resolution. b. minimum separation. c. fixed diameter. d. separation.

Answer 104

a. spatial resolution.

Question 105

8. Contrast sensitivity refers to the noise graininess in an image. The _____of this contrast sensitivity value is commonly referred to as___ a. performance, quality b. reconstruction, performance quality c. inverse, signal-to-noise ratio d. signal strength, signal-to-noise ratio

Answer 105

c. inverse, signal-to-noise ratio

Question 106

9. Features in an image that are not present in the test Object are called: a. mechanical inaccuracies. b. material densities. c. partial voluming effects. d. artifacts.

Answer 106

d. artifacts.

Question 107

10. Using a reference standard, a correlation between CT value and can be established because the X-ray attenuation coefficient is dependent on both and a. atomic number, density, Cr value b. material density, density, atomic number c. X-ray attenuation coefficient, density, CT value d. atomic number, X-ray energy, thickness

Answer 107

b. material density, density, atomic number

Question 108

11. The sensitivity to fine detail of CT systems is a function of. a. source sel ection. b. detector aperture sizes. c. spatial resolution and contrast sensitivity d. beam width.

Answer 108

c. spatial resolution and contrast sensitivity d. beam width.

Question 109

12. Reference standards are used to evaluate various characteristics of a CT system. Reference standards that represent actual parts and have known discontinuities are used: a. a to monitor day-to-day testing sensitivity. b. to characterize discontinuities. c. as replacement parts. d. to evaluate the radiation source.

Answer 109

a. a to monitor day-to-day testing sensitivity.

Question 110

1. A provider or user Of X-radiography should consider neutron radiography if: a. the X-ray could damage the item. b. the X-ray equipment cannot be moved. c. the X-ray and other NDT provides insufficient in formation. d. the X-ray of high quality is too espensiye.

Answer 110

c. the X-ray and other NDT provides insufficient in formation.

Question 111

2. What makes neutron radiography uniquely useful? a. The interaction of neutrons and X-rays with matter is fundamentally different. b. Neutrons are easily shielded. c. Personnel safety is easier than with X-rays. d. Imaging neutrons require less sophisticated equipment.

Answer 111

a. The interaction of neutrons and X-rays with matter is fundamentally different.

Question 112

3. Neutron radiography is uniquely suited to detection of corrosion in aircraft because: a. neutrons are easier to image with light elements and metals. b. neutrons are strongly attenuated by aluminum. c. neutrons are strongly attenuated by magnesium and lead, d. neutrons are strongly attenuated by hydrogen and water.

Answer 112

d. neutrons are strongly attenuated by hydrogen and water.

Question 113

3. A neutron radiography service center typically requires: a. a high flux nuclear reactor. b. a typical research reactor or smaller. c. a reactor design less than 20 years old. d. a spallation source with low gamma.

Answer 113

b. a typical research reactor or smaller.

Question 114

5. The neutron energy most commonly used in nondestructive testing is: a. cold. b. thermal. c. fast. d. slow.

Answer 114

b. thermal.

Question 115

6. All of the following are neutron-imaging processes except: a. X-ray film Without conversion screens. b. gadolinium converter with X-ray film. c. neutron-sensitive storage phosphor, d. dysprosium or indium foils activation transfer to film.

Answer 115

a. X-ray film Without conversion screens.

Question 116

7. If X-ray is inadequate for a diagnosis, a recommended step is; a. repeat X-ray using gadolinium intensifying b. reduce L/D ratio one half and repeat X ray. c. schedule at a neutron radiography user center for an experiment. d. seek a standard neutrón radiography provider and discuss options.

Answer 116

d. seek a standard neutron radiography provider and discuss options.

Question 117

8. When selecting a neutron radiography service, expect a. only film imaging is available, not digital. b. only plain (20) neutron radiography is available, not tomography. c. the item sent cannot be returned. d. film digital, and computed tomography may be available.

Answer 117

d. film digital, and computed tomography may be available.