eBook Rt20level20ii Answers Htm

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RADIOGRAPHY TESTING LEVEL II-Answers

1. Answer

A No, they are made of metal.

B Correct! Beryllium allows all but the longtest wavelength x-

rays to pass through it.

C No, they are made of metal.

D No, even a thin layer of lead would greatly reduce the penetrating power of a low voltage machine's x-ray beam.

2. Answer

A. Mono is the prefix for one not narrow.

B. Heterogeneous means "many" mono means "one".

C. Characteristic radiation can be made up of one or many

different wavelengths. The prefix mono - means one.

D. YOU'RE RIGHT! Mono means one or single and chromatic

refers to the color or wavelength.

3. Answer

A. The focus cup is at the cathode and where the electrons are

produced.

B. The filament is at the cathode where electrons are generated

and travel from.

C. CORRECT! The focusing cup, filament, and cathode produce and

direct the electron beam.

D. This is where the electrons are produced and begin their

acceleration.

4. Answer

A. ALRIGHT! Cobalt is suitable for radiographing steel above

3-4 inches thick and has a rated penetrating power of 1.17

and 1.33 MeV respectively.

B. Far too weak. Thulium-170 has a rated penetrating power

of 84KeV.

C. Too weak. Iridium-192 has a rated penetrating power of 400KeV and is limited to 3 inches of steel.

D. Stronger than Iridium-192 Cesium-137 has a rated penetrating

strength of 662 KeV and is limited to examining steel up to

approximately 3 inches thick.

5. Answer

A. Much more.

B. More.

C. CORRECT!

D. Less.

6. Answer

A. YES! The thickness, atomic number, and material

density all effect the absorption of both gamma and X-rays.

B. Young's modulus is the ratio of the stress and strain of an

object.

C. Poisson's ratio deals with the distribution of strain and

stress within an object.

D. The specific activity does relate to the penetrating power

and absorption of gamma radiation.

7. Answer

A. They are not useful in generating the high voltages needed

for X-ray production.

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B. X-ray tubes contain a vacuum whose efficiency would be

adversely affected by the introduction of gases.

C. Masks are lead foil screens with holes cut in them in the

shape of the object being radiographed.

D. YES! This phenomena is used in pocket dosimeters and other

detection equipment.

8. Answer

A. Atomic number does not effect electron velocity. Electrons for all atoms are identical.

B. Atomic number does not effect electron velocity. Electrons

for all atoms are identical.

C. RIGHT ON! The voltage potential between the cathode and

anode is responsible for electron velocity.

D. The rectifier converts AC to DC and does not control

electron velocity.

9. Answer

A. CORRECT! Also note the faster the film the larger the individual

silver salts (grains). Thus fast film tends to be grainier.

B. Streaks are usually caused by a contaminated or weak

developer during processing.

C. Spots are not grains and can be caused by various other factors mainly dust and water spots.

D. This is usually a result of weak or contaminated fixer.

10. Answer

A. Cobalt-60's characteristic gamma rays are rate at 1.17 MeV and

1.33 MeV, running second in this field.

B. A 220kVp X-ray tube has a beam strength of approximately

.220MeV dead last in this race.

C. YES! A 15MeV X-ray betatron is a linear accelerator

whose beam strength is 12 times that of Cobalt the next most

penetrating source on this list.

D. Iridium-192 characteristic gamma rays on average are

approximately .4 MeV in strength a distant third in this race.

11. Answer

A. AFFIRMATIVE!

B. Way too high.

C. Too high measured in hours not minutes.

D. Way too less. This is only .0004 roentgens per hour.

12. Answer

A. Angle inclination can vary with tube design.

B. It is maintained at a high positive voltage.

C. A large spot creates a wide beam not a narrow one.

D. O.K.! A smaller focal spot creates a narrower beam of X-

radiation and raises the definition of the radiograph.

13. Answer

A. This is where the target is located.

B. ABSOLUTELY! The filament is the source of the electrons and

the focusing cup aims them onto the target anode.

C. The rectifier converts AC to DC current and does not contain

the filament or focusing cup.

D. This supplies the high voltages needed to accelerate the

electrons and does not house the filament or focusing cup.




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14. Answer

A. A millicurie equals 1/1000th of a curie which is equivalent

to 37,000,000,000 atomic disintegration per second.

B. A gamma is not a unit of measurement. It refers to the

radiation given off by the atomic disintegration within

radioisotopic nuclei.

C. CORRECT! 0.001293 grams of dry air is equivalent to one

cubic centimeter of dry air at sea level.

D. A curie is equal to 37,000,000,000 atomic disintegrations per second and is used in reference only to gamma rays.

15. Answer

A. This is a measure of penetrating strength.

B. VERY GOOD! The curies per gram is the measure of specific

activity. One curie equals 37,000,000 disintegrations per

second.

C. The roentgen measures radiation present in the air, either

gamma or x-radiation.

D. This is not terminology used in radiography much less for

specific activity. Way off.

16. Answer

A. Thulium-170 has a half-life of only 129 days. Ranked third here.

B. Cobalt-60 has a half-life of 5.3 years the second longest in

this group.

C. Iridium-192 has a half-life of only 73 days the shortest of

this group.

D. PRECISELY! Cesium-137 with a half-life of 30 years in the

longest of this group.

17. Answer

A. Less than 3% of the energy is converted here.

B. Less than 3% of the energy is converted here.

C. Less than 3% of the energy is converted here.

D. EXACTLY! For example: only 3% of a 300 keV X-ray tube's total energy is converted to X-rays. The other 97% is

released as heat.

18. Answer

A. The film has a speed, but this curve does not.

B. Latitude is the range of thicknesses that can be adequately

recorded on the radiograph and is related to the slope of this

line.

C. CORRECT!

D. The density is the degree of blackness of an area of a

radiograph.

19. Answer

A. Not necessarily.B. YES! X-ray films with a narrow latitude by definitions are

high contrast.

C. Usually a wide latitude means a slow film speed.

D. There is one correct answer. Narrow latitude films have a

high contrast by definition.

20. Answer

A. The parts of an X-ray tube do not need lubrication.

B. Oil does not disgnificantly attenuate or absorb x-radiation.

C. Circulating oil does not effect the voltage needed to




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produce X-rays.

D. GOOD! Because 97% or more of the energy of an X-ray tube is

given off as heat circulating oil is used for cooling.

21. Answer

A. The focal spot is not related to penetrating power.

B. TRUE! The smaller the focal spot the better the definition.

C. The size of the focal spot does not effect the film or subject contrast.

D. Density is the degree of blackness of an area of a

radiograph and is not a function of the focal spot.

22. Answer

A. This will increase the exposure time needed, but will not

affect contrast.

B. This will reduce the exposure time needed, but will not

affect contrast.

C. YOU BET! Shorter wavelength X-rays are more penetrating ,

but less photographically active and produce high contrast

radiographs.

D. This will increase the radiographic density, but will not

affect overall contrast.

23. Answer

A. Lead films do not fluoresce, they emit photographically active

atomic particles to increase density.

B. They do absorb scatter radiation to prevent fogging of the

radiograph, but to increase density.

C. This is true, but what does this have to do with density which

is a function of exposure.

D. CORRECT! These electrons are photographically active and

intensify the exposure and increase the darkening of the film.

24. Answer

A. Oil or water circulation is used to dissipate heat.B. YOU'RE RIGHT! Do to the high voltages involved an

electrically insulated casing is required to protect the

operator.

C. Secondary radiation does not effect the X-ray tube, but will

cause film fog.

D. No, the rectifier converts ac to dc current and a shockproof

casing has no relation to its efficiency.

25. Answer

A. CORRECT! The K stands for kilo, which equals 1,000.

250KV = 250,000 Volts

B. Effective voltage! Not conventional radiographic term. What

does the "p" stand for?

C. Too much! What is rms?D. What is KVp the acronym for? K stands for kilo or 1,000.

What does the "p" stand for?

26. Answer

A. Iron core transformers are not used for higher voltage X-ray machines.

B. No, this supplies the current necessary to heat the filament

to create the gaseous cloud of needed electrons.

C. CORRECT!

D. This is too general.




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27. Answer

A. Transformers used to step up the voltage level of available

on-line power.

B. YES! The half wave rectifier converts the ac to pulsing dc

current.

C. An anode is the positive (+) side of the voltage potential

created across the tubes interior and is where the target is

located.

D. The cathode is the negative (-) side of the voltage potential created to the accelerate the electrons and is where the

filament is located.

28. Answer

A. Two percent of 2.5 inches does not equal .5 inches.

B. This equals .0025 inches. Is this 2 percent of 2.5 inches?

What is 2.5 x .02?

C. This equals .005 inches. Is this 2 percent of 2.5 inches or

.02 x 2.5?

D. CORRECT! 50 mils. equals .05 inches or 2 percent of 2.5

inches, computed as 2.5 x .05 or 50 mils., or 50 thousandths

of an inch.

29. Answer

A. Correct! yes the valve tubes are used to convert ac to

pulsing dc current.

B. This is accomplished by a large switch.

C. This is done by the filament transformer.

D. No! There are no adjustments for target size. The target

size is static, although the focal point can vary.

30. Answer

A. Too short. 36 inches equals 3 ft., 24 inches equals 2 ft.

squared each. What does 4 / 9 x 10 equal?

B. Yes! 3 ft. squared equals 9, and 2 ft squared equals 4.

4 /9 = 4/9 x 10 = 4.444...C. Too long. What is 4 / 9 x 10?

D. Way too long. What is 4 / 9 x 10?

31. Answer

A. This can cause the radiograph to be foggy.

B. This is highly unlikely.

C. Yes! The electrical discharge of static electricity exposes

crystals.

D. This is always necessary in producing radiographs with X-ray

equipment that uses a shutter at the tube port.

32. Answer

A. CORRECT! This increases the number of electrons produced and

is a function of amperage.B. This does not effect the tube voltage, but is used to change

the focal spot.

C. This adjusts the voltage potential across the tube and the

speed of the bombarding electrons, but not the amperage.

D. This controls exposure time not current.

33. Answer

A. Less contrast.

B. CORRECT! High penetrating short wavelength X-rays are less

photographically active.




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C. Lesser amounts of scatter radiation is created due to shorter

wavelength X-rays being produced.

D. There is one correct answer. High-energy radiographics have

less contrast.

34. Answer

A. They reduce secondary radiation which are the longer

wavelength X-rays.

B. They filter longer wavelengths and allow the shorter wavelengths to pass with little attenuation.

C. Intensity is controlled by the voltage or KVp knob.

D. Yes! The short wavelengths pass through with minimal

attenuation. The longer wavelengths "softer" X-rays

create scatter radiation and film fog.

35. Answer

A. Never use aluminum as a substitute for steel. Penetrameters

should be made of the same base metal as the specimen.

B. No! An aluminum penetrameter should not be used in place of

the specimens base metal which is steel.

C. VERY GOOD! 10 mils. is the equivalent to .01 inches or 2

percent of .5 inches.

D. Wrong size too thin. Must be made of specimen's base metal.

36. Answer

A. What about the intensity of the beam?

B. What about the quality of the X-rays produced?

C. PRECISELY! Kilovoltage controls the wavelength of the

X-rays produced which affects both the quality and intensity

or penetrating power.

D. At least one is correct. Remember, kilovoltage controls the

minimum wavelength of the X-ray spectrum produced.

37. AnswerA. EXACTLY! The longer wavelength "soft" X-rays increase

scatter radiation and can fog the resulting radiograph.

B. No, the penetrating short wavelength "hard" X-rays are only

slightly attenuated by filters.

C. Backscatter is controlled by placing a lead foil sheet

behind the specimen, not in front facing the source.

D. Intensity is only slightly affected because the shorter

wavelength X-rays pass through the filter material virtually

unaffected.

38. Answer

A. They do not attenuate radiation enough for this.

B. OF COURSE! By releasing electrons that photographically react

with the film.C. No, they increase the photographic action of the X-rays

slightly and permit the use of slower speed films.

D. Graininess is a factor mainly dependent on film speed and

often screens will increase graininess.

39. Answer

A. Subject contrast is the difference between two area

densities of a radiograph and do not pertain to thickness.

B. Sensitivity and range of thickness are not connected.

Sensitivity is a measure of the smallest detail that can be




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accurately resolved.

C. GOOD! The range of thickness over which densities are

satisfactory for interpretation is known as latitude.

D. Definition is the line of demarcation between area of

different densities.

40. Answer

A. Natural isotopes are not necessarily radioactive and

radioisotopes for gamma radiology are man made.B. TRUE! Thulium-170 and radium are rarely used.

C. Radium was used frequently for medical radiology at the turn

of the century, but is not used often today.

D. Thulium -170 is far too weak a source for industrial

most radiography.

41. Answer

A. It is directly proportional to the size of the focal spot.

B. CORRECT!

C. It is inversely proportional to the source-to-object

distance and directly proportional to the object-to-film

distance.

D. It is directly proportional to the size of the focal spot and the object-to-film distance.

42. Answer

A. This increases definition.

B. SURE! The increase in material between the discontinuity

and the film reduces the definition.

C. This increases definition.

D. This would increase the definition of the discontinuity by

reducing the distance to the film.

43. Answer

A. YOU'RE RIGHT!

B. This controls the penetration power of the X-rays produced, but is not a factor in the tubes inherent filtration.

C. This is not a factor in inherent filtration in an X-ray

tube, but it does control the intensity of the X-rays reaching

the specimen.

D. The material used as a target controls the efficiency of the

tube, but does not play a role in inherent filtration.

44. Answer

A. The opposite is true.

B. They have faster speeds.

C. CORRECT!

D. Just the opposite is true.

45. AnswerA. ALRIGHT!

B. Just the opposite is true.

C. The effective energy is not a direct factor controlling

definition. This is more a factor of focal spot size, source-

to-object distance and object-to-film distance.

D. Film speed is unchangeable and is set for each type of film.

46. Answer

A. YES! More Cobalt-59 is converted to Cobalt-60.




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B. The atomic number of Cobalt is always 27.

C. This is incorrect terminology. Cobalt-60 releases gamma rays

because of the neutron bombardment.

D. Young's modules is the radio of stress to strain in an object.

47. Answer

A. Wrong, it's denser than copper.

B. Wrong, carbon is not used in X-ray radiography.C. Wrong, carbonide is a compound not an element. Only dense

elements are used for targets.

D. RIGHT! Tungsten is commonly used because of its density and

high melting point.

48. Answer

A. Rotation of the anode target does not affect the intensity

of the X-rays produced.

B. Rotation and target shape do not affect X-ray quality. KV

controls the X-ray quality.

C. CORRECT! By cooling the target anode rotation allows higher

voltages or loads to be used without over heating and

melting the target.

D. One answer is correct. Rotation acts to cool the target during operation.

49. Answer

A. This is a Van de Graff generator which does not use magnets.

B. Linear accelerators guide and accelerate electrons in a line

not a circle.

C. YES!

D. The device described in the question is not a tube.

50. Answer

A. CORRECT! Specific activity is measured by curies per gram,

thus, if source strength is equal the higher specific

activity source will be smaller and weigh less.B. Half-life is not a factor of specific activity which is

measured by curies per gram. If the source strengths are

equal, then both are made of the same element and have equal

lives.

C. The wavelength of gamma rays is specific according to the

radioisotopic element and are not a function of specific

activity.

D. Specific activity is measured by curies per gram, and the

opposite is true.

51. Answer

A. X-ray tubes contain no gas and are vacuum tubes.

B. A what! This is not a radiographic term. X-ray tubes lack

any gas inside and contain a vacuum.C. X-ray tubes contain a vacuum inside and are not gas filled.

D. ABSOLUTELY RIGHT! X-ray tubes contain a vacuum.

52. Answer

A. Results are reproducible and screens are not replaced

frequently.

B. CORRECT! The limited brightness and grainy image make

fluoroscopy less sensitive.

C. Fluoroscopy is a fast real-time imaging method whose

initial cost is only slightly higher.




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D. Fluoroscopy can use short wavelength X-rays which are high

intensity, but the image is grainy and weak.

53. Answer

A. A densitometer reads a radiograph's density and not

equipment quality.

B. CORRECT!

C. This may be used to measure sensitivity, but is not a

standardized way to measure equipment quality.D. Reference standards are not a measure of equipment quality.

Equipment quality is measured by the resulting radiographs

of a standardized object of a specific thickness with holes

of varying sizes.

54. Answer

A. This is a circular electron accelerator used to produce X-

rays.

B. It is an amplifier, but not for electrons.

C. CORRECT!

D. This is an Van de Graff generator used to create high

voltages.

55. AnswerA. It should be from the smallest focal spot possible.

B. It should be as far away as practical.

C. The film should be as close to the object being radiographed

as possible.

D. CORRECT! Any other angle increases the geometric distortion

of the object being radiographed.

56. Answer

A. This ratio is not conducive to producing radiographs of any

quality.

B. CORRECT! This would increase definition.

C. Magnetic fields do not effect X-rays or gamma rays.

D. This is not a necessary request.

57. Answer

A. Yes, but what about the atomic number of the material?

B. Yes, but what about the thickness and density of the

material?

C. CORRECT!

D. There is at least one correct answer.

58. Answer

A. CORRECT! Shorter wavelength X-rays are produced and their

alternation is more dependent upon material thickness.

B. This will increase the quantity of X-rays, But will not

affect their penetration and absorption.

C. Just the opposite is true.D. A filter will eliminate the longer wavelength X-rays, but

will not affect the absorption of the shorter wavelengths.

59. Answer

A. This is a function of exposure time vs. density.

B. This is not conventional terminology in radiographic testing.

C. Radiographic contract is the measure of the difference between

the density values from to areas of a radiograph.

D. CORRECT!




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60. Answer

A. The cathodes composition does not affect the load that can

be handled by the target anode.

B. CORRECT!

C. The distance between the cathode and the anode is not a

factor affecting load, but heat dissipation is.

D. The voltage waveform is not a factor, but heat dissipation

and the focal spot are.

61. Answer

A. Intensifying screens are placed in front of the film.

B. CORRECT!

C. Only one is correct. Note that is placed at the back of the

screen.

D. At least one of the answers is correct.

62. Answer

A. CORRECT!

B. No, it is used to determine the size of something.

C. A lead sheet will filter scatter radiation, but is the

pinhole for?

D. A lead sheet will harden the radiation by eliminating the

longer (soft) X-rays, but what is the pinhole for?

63. Answer

A. This is not cooling at all. What is used in an automobile

radiator for cooling?

B. Air does not offer the cooling efficiency needed.

C. CORRECT!

D. Rods are sometimes used, but no finned radiators. The

cooling system in most X-ray tubes uses a liquid coolant.

64. Answer

A. Specimens are inanimate objects in industrial radiography

and unlike humans do not move.

B. This has no affect on the subject contrast. It is used to eliminate secondary radiation from fogging the film.

C. No, shorter wavelength X-radiation is increased by

increasing the KV.

D. CORRECT!

65. Answer

A. Raising the KV, but not by using fluorescent screens which

will increase mottling.

B. Using lead foil screens yes, but not by lowering KV.

C. CORRECT! Raising KV produces shorter wavelength X-rays and

the lead screens filter out the less penetrating shorter

wavelengths.

D. Neither lowering the KV or using fluorescent screens is

correct. You must raise the KV and use a different type of screen.

66. Answer

A. Cobalt-60, which is rated at 1.33MeV is less sensitive and

much too powerful for radiographing one inch of steel.

B. CORRECT! Cobalt-60 is much to powerful.

C. Lead foil screens should be used.

D. The opposite is true.

67. Answer




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75. Answer

A. High film density is caused by overexposure and

overdevelopment.

B. CORRECT!

C. Fogged film is caused by scatter radiation.

D. Low film density is usually caused by underexposure or

underdevelopment.

76. AnswerA. Special glasses are not needed in fluoroscopy, and would not

reduce fatigue anyway.

B. Filters have no effect on operator fatigue.

C. Background light intensity should remain at one intensity and

not vary.

D. CORRECT!

77. Answer

A. Higher.

B. Higher.

C. CORRECT!

D. Much higher.

78. AnswerA. Graininess of the film is not significantly affected.

B. Graininess of the film is not significantly affected.

C. Graininess of the film is not significantly affected.

D. CORRECT!

79. Answer

A. Mottling is caused by excessive defraction of the beam, not

exposure time.

B. Mottling is caused by excessive defraction of the beam, not

exposure time.

C. CORRECT!

D. Ultraviolet rays will fog film, but are not the cause of

mottling.

80. Answer

A. It is less sensitive and grainier.

B. CORRECT! It is also less sensitive.

C. Radiographis are not inherently bright. Their brightness

depends on the intensity of the viewing light.

D. There is a great amount of difference between the two, for

instance one is filmless and the other is not.

81. Answer

A. Correct!

B. It is intensity multiplied by the time.

C. It is intensity multiplied by the time.

D. It is intensity multiplied by the time.

82. Answer

A. Changing from a high contrast film to a low contrast film

would change film density as well as changing film spee

B. CORRECT! The size of the film is not a factor influencing

film density.

C. Exposure directly influences a radiograph's density.

D. Intensifying screens are used to increase radiographic

density.




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83. Answer

A. Much more.

B. More.

C. CORRECT!

D. Less.

84. Answer

A. No, it is a type of shadowing.

B. CORRECT! The maximum amount of penumbral shadow undetectable by the human eye is 0.020 in.

C. No, it is a type of shadowing.

D. No, it is a type of shadowing.

85. Answer

A. No, it is not under stress, but the target does get very

hot.

B. Melting point yes, magnetic strength no.

C. Neither is a factor, remember the best target material is

made from the denser elements.

D. CORRECT! Targets made from elements with high atonic

numbers are more efficient and high operating temperatures

require a high melting point.

86. Answer

A. An exponent is involved, but it is the square of the

distance.

B. Not the square root, it's the square of the distance!

C. CORRECT! This is known as the inverse square law.

D. No, it's the inverse square law which does not involve

scattered radiation.

87. Answer

A. CORRECT! Or .5 x 1.4 x 1.0

B. What is half of 1.4?

C. No, what is .5 x 1.4 x 1.0?

D. No, what is half of 1.4?

88. Answer

A. This controls the size of the penumbral shadow and

sharpness.

B. Adjusting the milliamperage varies the number of X-rays, but

does not change the penetration power of the X-rays produced

or the image contrast.

C. CORRECT! Adjusting the KV increases or decreases the

penetrating power of the X-rays produced and thus the

resulting image contrast.

D. Changing the focal spot size can increase or decrease

sharpness, but does not effect image contrast.

89. AnswerA. No, it has no effect on film speed, this is set in the

manufacture.

B. CORRECT! Fogging occurs because of a chemical change in the

silver bromide crystals.

C. No, mottling is caused by not using lead screens during

exposure to reduce secondary radiation created by beam

diffraction.

D. No, this is caused by static electricity generated by

friction.




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90. Answer

A. No, definition is the line of demarcation between two areas

of different densities.

B. CORRECT! The instrument used to measure film density is

called a densitometer.

C. No, film contrast is the inherent ability of a film to show

a density difference for a given change in film exposure.

D. Radiographic contrast is the comparison between film densities

for different areas of a radiograph.

91. Answer

A Sensitivity is measured by using pentrameters.

B. It is a function of density and exposure, but this is not its

proper name.

C. CORRECT!

D. X-ray intensity is not a function used in this film

characteristic curve.

92. Answer

A. How about scattered radiation and its fogging effect?

B. What about the thickness of the specimen being radiographed?

C. What about radiation quality?

D. CORRECT!

93. Answer

A. Of course, this is not a regulation, it is a necessity!

B. CORRECT!

C. No, heavy dense metal casings are inherently shockproff.

D. No, they are a lot thicker than conventional containers and

are composed of lead or spent uranium.

94. Answer

A. A film badge measures the cumulative radiation dose over a

period of time and is worn by personnel.

B. This like the film badge measures the accumulative dose

received by personnel over a period of time.C. CORRECT! A geiger counter is more sensitive and gives an

immediate indication of radiation.

D. No, this measures personnel exposure to radiation a

period of time.

95. Answer

A. Aluminum is more penetrable than lead and would be

expensive to use because of the thickneses needed.

B. CORRECT! Concrete is not only effective, but inexpensive as

well.

C. Steel is dense and would be adequate, but considering the

thickness needed it would be very expensive.

D. Boron is less dense than all of the above and would the

least effective barrier.

96. Answer

A. CORRECT!

B. Radiographic definition is the line of demarcation between

areas of different densities.

C. Radiographic contrast is the comparison between film

densities for different areas of a radiograph.

D. Subject contrast is the ratio of X or gamma ray intensities

transmitted by two selected portions of the specimen.




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97. Answer

A. Subject contract is the ratio of X or gamma ray intensities

transmitted by two selected portions of the specimen.

B. Radiographic definition is the line of demarcation between

areas of different densities.

C. Radiographic contrast is the comparison between film densities

for different areas of a radiograph.

D. CORRECT!

98. Answer

A. The fluoroscopy process is capable of displaying an image on

a screen by conversion of X-radiation into visible light.

B. No such thing!

C. CORRECT! Stereo means two.

D. Parallel involves two or more linear paths, but can also be

an infinite number of paths or lines. What prefix above

means two?

99. Answer

A. Stereoradiography gives the viewer a three-dimensional

effect by using two radiographs of a specimen and a

stereoscope.

B. No such thing. Zero means zero and this is a meaningless term that describes a method which does not exist.

C. The fluoroscopy process is capable of displaying an image on

a screen by conversion of X-radiation into visible light.

D. CORRECT!

100.Answer

A. Yes, but often in only certain areas.

B. Yes, but often without desireable effects.

C. CORRECT!

D. Reticulation is not caused by developer flow.

101.Answer

A. Evaporation is not a factor. The diminishing effect is caused by contamination.

B. No, but the solution does

become contaminated.

C. CORRECT! This contamination results in the diminishing

activity of the solution.

D. Once dissolved the active ingredients do not settle out, but

do become contaminated.

102.Answer

A. More

B. CORRECT!

C. No, it has to with tank size.

D. No, it has to with tank size.

103.Answer

A. What about Compton absorption?

B. Photoelectric absorption is also possible.

C. CORRECT!

D. At least one is correct.

104.Answer

A. The screen cannot be "recharged".

B. CORRECT!

C. This may bring back some of its brilliance, but is dangerous




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17/23

C. A lot less.

D. CORRECT!

112.Answer

A. CORRECT!

B. Yes they are.

C. Yes it can.

D. Yes it does with voltage.

113.Answer

A. This is caused by the specimen and would not image the back

of the cassette.

B. This results in areas blacking out or becoming dense.

C. No, high X-ray intensity results in poor subject

contrast.

D. CORRECT! Radiation scattered onto the back of the film

cassette causes this, a lead "B" is placed on the

back of the film to measure back scatter radiation.

114.Answer

A. This is usually caused by too high of a kilovoltage setting

or by using the wrong type of film.

B. CORRECT!C. Fogging is caused by scatter radiation or heat damage to the

film.

D. It will produce poor resolution, but the overall appearance

is what we're referring to here.

115.Answer

A. CORRECT! Calculated as 64 x 1/2 x 1/2 x 1/2 = 8

B. There are three half valve layers of lead in a 1.5 inch

specimen or 1/2 x 1/2 x 1/2 = 1/8. Does 64 x 1/8 = 21 1/3?

C. There are three half valve layers of lead in a 1.5 inch


D. There are three half valve layers of lead in a 1.5 inch


116.Answer

A. The nature of the specimen can greatly affect subject

contrast.

B. The radiation quality greatly affects subject contrast.

Hard X-rays produce less contrast than do soft X-rays.

C. CORRECT! The type of film used has inherent contrast

qualities known as "film contrast" which has no relation to

subject contrast.

D. Intensity and distribution of scattered radiation greatly

affects subject contrast. Scattered radiation reduces

subject contrast.

117.AnswerA. Not long enough. Use the inverse square law which states:

D2 squared / D1 squared = new exposure time. Or 5 squared /

4 squared x 60 = new exposure time.

B. CORRECT! According to the inverse square law 5 squared/4

squared = 1.5625 x 60 = 93.75 or 94 seconds.

C. Far too short. Use the inverse square law which states D2

squared / D1 squared x time = new exposure time.

D. Far too short. Use the inverse square law which states D2

squared / D1 squared x time = new exposure time.




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118.Answer

A. This would increase the photographic action, but not film

latitude.

B. Placing the same film one on top another has no effect on

film latitude which is an inherent property for each film

type.

C. CORRECT! Since latitude is an inherent property, as is film

contrast, the only way to increase it is to use two films

with different speeds.D. No, one answer is a practical means of increasing latitude.

119.Answer

A. More.

B. CORRECT! Once two or three replenisher supplements have

exhausted the developer it becomes too contaminated to

revive.

C. Less.

D. Less.

120.Answer

A. A higher kilovoltage setting decreases contrast.

B. The 50 KV exposure would have a greater latitude.

C. CORRECT! Because the kV X-rays are harder and have less photoactive capabilities.

D. It would have lower contrast.

121.Answer

A. More.

B. CORRECT!

C. Less.

D. Much less.

122.Answer

A. CORRECT! And it's measured as curies per gram.

B. The quality of the source is irrelevant to concentration

which is measured by curies per gram.C. Atomic weight is not directly related to source

concentration which is measured by curies per gram.

D. The degree o0f concentration does not affect the source half

life.

123.Answer

A. Does not increase or decrease the generation of short

wavelength X-rays.

B. Does not increase or decrease the generation of short

wavelength X-rays.

C. It plays no important role in scatter radiation.

D. CORRECT! Filtration of such a powerful X-ray beam at the

tube offers no improvement in the radiographic quality.

124.Answer

A. The curie is equivalent to 37,000,000,000 atomic

disintegrations per second, but is not a measurement of gamma

ray energy.

B. The Roentgen is a measure of the amount of radiation present

in the air by measuring its ionizing effect, but is not a

measurement of gamma ray energy.

C. Half-life is a term that describes the time in which it

takes for one-half of the atoms of a radioisotope to decay.

D. CORRECT! KeV and MeV are measurements of gamma ray energy.




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125.Answer

A. What about the material density of a specimen?

B. What about the voltage range of the machine?

C. What about the thickness of the material?

D. CORRECT! Part thickness, material, and voltage range of the

X-ray machine all influence film selection.

126.AnswerA. Lowering kilovoltage decreases X-ray energy, but does not

increase intensity.

B. CORRECT! Raising tube current or milliamperage increases X-

ray intensity.

C. This would lower the intensity of the beam according to the

inverse square law.

D. Decreasing tube current lowers X-ray intensity.

127.Answer

A. What about absorbing longer wavelength radiation?

B. What about intensifying the photographic effect of the

primary more than the scattered radiation?

C. What about increasing the photographic action on the film?

D. CORRECT!

128.Answer

A. This will reduce mottling, but if kilovoltage is already at

its peak, using lead foil screens will also reduce mottling.

B. Raising the kilovoltage and increasing X-ray penetration

power will also reduce mottling.

C. CORRECT! Both will reduce mottling by decreasing the amount

of diffraction.

D. At least one is correct. Mottling is caused by the

defraction of less penetrating longer wavelength X-rays.

129.Answer

A. This is not a term used in radiography.B. CORRECT! By controlling these factors the penumbral shadow

can be reduced and sharpness increased.

C. X and gamma rays are not focused on the film plane during

radiography like visible light is during photography.

D. One is correct. X and gamma rays are not focused like visual

light they are attenuated by varying degrees.

130.Answer

A. No a device called a colliminator, the shape of the target,

and the tube window are designed to control beam width and

direction.

B. CORRECT! Intensity is controlled by milliamperage, quality

by kilovoltage, and exposure duration by a timer or switch.

C. There is no Film Focal Distance in radiography this is a photographic term. Besides the film is in fixed cassettes

positioned as close to the specimen as possible.

D. No, this is done by the rectifier and is not directly

controlled by the operator.

131.Answer

A. No this will not harm them and periodic cleaning is actually

beneficial.

B. CORRECT! Sunlight and ultraviolet light drain the amount of

fluorescent material available for visible light production




20/23

during radiography.

C. This can lead to screen damage, but is not necessarily easy.

D. No, the screens can be used many times for X-radiography.

132.Answer

A. Density is a direct result of this change, but only after

processing.

B. Sensitivity is a measure of the ability to undergo this

change.C. CORRECT! This is a chemical change which is not apparent

until the film is processed.

D. The characteristic curve is a graphical representation of

the emulsions ability to undergo this chemical change over a

specific range of exposure.

133.Answer

A. Ten curies is ten times stronger not one tenth as strong.

B. Much less. It is ten times as intense, not 100 times.

C. Much more. Ten curies would be ten times as intense.

D. CORRECT! Since the distance is equal a ten curie source is

exactly ten times as intense as a one curie source.

134.AnswerA. Source activity is not a factor.

B. Size of film is not a factor.

C. Source activity is not a factor.

D. CORRECT! All three are important quality factors.

135.Answer

A. Porosity causes less attenuation of the beam and appears

darker in the image.

B. Slag inclusions are less dense and appear as dark images.

C. CORRECT! Tungsten is more dense and attenautes the beam

more than the surrounding material resulting in a very light

image, and is irregular in shape.

D. This would appear as a dark image.

136.Answer

A. CORRECT! This in essence reduces its physical size as it

appears from the viewpoint of the specimen.

B. This will reduce backscatter, but will not reduce the size

of the penumbral shadow.

C. This will increase image contrast and graininess but, does

not reduce the penumbral shadow.

D. Decreasing the exposure time would not reduce the penumbral

shadow and improve image quality.

137.Answer

A. Excessive density is caused by incorrect exposure time, high

film speed, or high beam intensity.B. CORRECT! A lead backscatter is attached to the back of the

film to measure backscatter and when exposed results in

a light image.

C. Kilovoltage controls scatter radiation, but the "B" image is

from a specific type of scattered radiation.

D. What does film handling have to do with backscatter being

imaged on the film?

138.Answer

A. No, the weight of an electron is insignificant and would not




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increase the atomic weight by 1.

B. CORRECT! And thus increases the atomic weight by one.

C. The capture of an additional proton would change the Cobalt,

but not to radioactive Cobalt 60.

D. Contamination by which of the above atomic particles?

139.Answer

A. It receives the same processing as the slower speed film.

B. The increased graininess of the faster film does not increase resolution.

C. CORRECT! The resulting image is grainier.

D. One of the answers is correct. Note that the faster speed

film will render a grainier image.

140.Answer

A. CORRECT! It has nothing to do with graininess although

faster (large grain) films usually have lower contrast than

slower (fine grain) films.

B. For a given radiation exposure showing graininess or no

graininess is not an inherent ability of film contrast.

C. For a given radiation exposure showing graininess or no

graininess is not an inherent ability of film contrast.

D. Showing a change in density is an inherent ability of film contrast for a given radiation.

141.Answer

A. Penetration refers to the ability of an X-ray beam to pass

through a material.

B. This is not a radiographic term. Absolution is a religious

term referring to the remission of sins.

C. CORRECT! Also referred to as attenuation.

D. Latitude, as in film latitude, refers to a film's ability to

resolve details over a specific exposure range.

142.Answer

A. Density is controlled mainly by the exposure time.B. Source size is not related to exposure.

C. Film size is determined by the area being radiographed and

is independent of source size, specimen thickness and

source-to-specimen distance.

D. CORRECT! All three are factors directly related to image

sharpness.

143.Answer

A. Sensitivity is the measure of the smallest detail that can be

imagined.

B. CORRECT! Latitude is the range of thicknesses that can be

adequately recorded on the radiograph.

C. This measure of accuracy of a radiograph is referred to as

its sensitivity.D. The source intensity is directly related to the range of the

thicknesses that can be recorded, but is not referred to as

the intensity of the source.

144.Answer

A. Way too shot, the half-life of Cobalt-60 is 5.3 years.

B. After 5.3 years the source would decay to 5 curies.

C. CORRECT! Since the half-life of Cobalt-600 is 5.3 years it

would take two half lives to reduce a 10 curies source to a

2.5 curie source.




22/23

D. One answer is correct. remember the half-life of Cobalt-60

is 5.3 years.

145.Answer

A. It involves the ejection of an electron which is a particle

and is not related to electromagnetic radiation of any kind.

B. The photoelectric effect does not involve cameras of any

kind.

C. CORRECT! Part of the photon energy is used in ejecting an electron and the remainder imparts velocity to the ejected

electron.

D. Only one answer is correct. Note that photoelectric effect

involves the ejection of an electron from its orbit.

146.Radiographic undercutting is caused by:

A. side scatter.

B. poor geometry.

C. lead screens.

D. free electrons.

146.Answer

A. CORRECT! It is also caused by internal scatter and can

present problems when radiographing irregularly shaped

objects.B. This does not necessarily cause undercutting.

C. Lead screens are used to reduce scatter radiation which

causes radiographic undercutting.

D. Radiographic undercutting is caused by radiation, not

electrons.

147.Answer

A. Just the opposite.

B. CORRECT! The stop bath is acid.

C. No, its not saline or a salt solution, although it reacts

with salt present in the photoemulsion, silver bromide

D. This is not a radiographic term.

148.Answer

A. The focal spot should be as small as possible.

B. The distance should be as far as possible.

C. The film should be as close as possible to the object being

radiographed.

D. CORRECT! Any angel other than 90 degrees increases

geometric distortion of the images on the radiograph.

149.Answer

A. CORRECT!

B. Less.

C. A lot less.

D. A whole lot less.

150.Answer

A. Much longer.

B. Longer.

C. CORRECT! Its rays have an average penetration power of

664 keV.

D. Much longer.

151.Answer

A. This refers to the amount of radiation needed to properly

expose a radiographic film.




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B. This is the range of thicknesses that can be adequately

recorded on a radiograph.

C. CORRECT!

D. No, but density is one of the functions used to plot the

graph.

152.Answer

A. Not necessarily so.

B. CORRECT! Narrow latitude films have high contrast.C. Can be true, but not always.

D. One answer is correct. Remember, narrow latitude films have

high contrast.

153.Answer

A. This is the actual area on which high velocity electrons are

focused to produce X-rays.

B. X-rays are not focused like light in conventional

photography.

C. CORRECT! The effective focal spot is either equal to or less

than the actual focal spot.

D. This can be caused by the source not being oriented at 90

degrees to the film plane.

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