UT Level 1 Flashcards

1
Q
  1. A second name for a compressional wave is:
    a. Lamp wave
    b. Shear Wave
    c. Longitudinal wave
    d. Transverse wave
A

C. Longitudinal Wave

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2
Q

A second name for Rayleigh Waves is:

a. Shear waves
b. Longitudinal Waves
c. Transvese waves
d. Surface waves

A

d. Surface Waves

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3
Q

A material used between the face of a search unit and the test surface to permit or improve the transmission of ultrasonic vibrations from the search unit to the material being tested is called:

a. Wetting agent
b. Couplant
c. Acoustic transmitter
d. Lubricant

A

b. Couplant

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4
Q

The piezoelectric material in a search unit or probe which vibrates to produce ultrasonic waves is called:

a. A backing material
b. A lucite wedge
c. A crystal
d. A Couplant

A

c. A Crystal

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5
Q

The number of complete waves which pass a given point in a given period of time (usually a second) is referred to as the :

a. Amplitude
b. Pulse length
c. Frequency of a wave motion
d. Wavelength of a wave motion

A

c. Frequency of a wave motion

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6
Q

When the motion of the particles of a medium are parallel to the direction of wave motion, the wave being transmitted is called a:

a. Longitudinal wave
b. Shear wave
c. Surface wave
d. Lamb wave

A

a. Longitudinal wave

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7
Q

The number 25 million cycles per second can also be stated as:

a. 25 kHz
b. 2500 kHz
c. 25 MHz
d. 25 uhz

A

c. 25 MHz

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8
Q

A term used in ultrasonic’s to expresss the speed at which sound waves pass through various substances is:

a. Frequency
b. Velocity
c. Wave length
d. None of the above

A

b. Velocity

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9
Q

An ultrasonic testing technique in which the transducer (crystal) is at an angle to the test surface is called:

a. Angle beam testing
b. Immersion testing
c. Contact testing
d. Through-transmission testing

A

a. Angle beam testing

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10
Q

Most commercial ultrasonic testing is accomplished using frequencies betweeen:

a. 1-25 kHz
b. 1-25 MHz
c. 1 - 1000 kHz
d. 15 - 100 MHz

A

b. 1 - 25 MHz

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11
Q

Which of the following test frequencies would generally provide he best penetration in a 300 mm thick specimen of the course-grained steel?

a. 1.0 MHz
b. 2.25 MHz
c. 5.0 MHz
d. 10 MHz

A

a. 1.0 MHz

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12
Q

All other factors being equal, which of the following modes of vibration has the greatest velocity?

a. Shear wave
b. Transverse wave
c. Surface wave
d. Longitudinal wave

A

d. Longitudinal wave

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13
Q

Sound waves of a frequency beyond the hearing range of the human ear are referred to as ultrasonic waves or vibration, and the term embraces alll vibrational waves of a frequency great than approximately:

a. 20 000 hertz (Hz)
b. 2 megahertz (MHz)
c. 2 kilohertz (kHz)
d. 200 kilohertz (kHz)

A

a. 20 000 hertz (Hz)

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14
Q

A disadvantage of using natural quartz crystals in a seach unit is:

a. It will dissolve in water
b. It is the least efficent generator of ultrasonic energy of all commonly used materials
c. it is mechanically and electrically unstable
d. It easily loses its operating characteristics as it ages

A

It is the least effiecent generator of ultrasonic energy of all commonly used materials

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15
Q

An advantage of using lithium sulfate in search units is :

a. It is one of the most efficient generators of ultrasonic enegy
b. It is one of the most effiecent receivers of ultrasonic energy
c. It is insoluble
d. It can withstand temperatures as high at 700’C

A

b. It is one of the most efficient receivers of ultrasonic energy

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16
Q

Which of the following search units would contain the thinnest quartz crystal?

a. A 1 MHz search unit
b. A 5 MHz search unit
c. A 15 MHz search unit
d. A 25 MHZ search unit

A

d. A 25 MHz search unit

Note: The thinner the crystal the higher the frequency

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17
Q

A material that converts electrical energy to or mechanical enegy or converts mechanical energy to the electrical energy is called:

a. Piezoelectic
b. Component
c. Attenuative
d. Ultrasonic

A

A. Piezoelectic

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18
Q

The Number 100,000 Hz can be written:

a. 10 kHz
b. 100 kHz
c. 100 MHz
d. 1000 kHz

A

b. 100 kHz

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19
Q

A general term applied to all cracks, inclusions, blow holes, etc. Which cause a reflection of sonic energy is:

a. A disperser
b. A discontinuity
c. A attenuator
d. A refractor

A

b. A discontinuity

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20
Q

Which of the following search units (probes) would contain the thickest quartz crystal?

a. A 1 MHz search unit
b. A 5 MHz search unit
c. A 15 MHz search unit
d. A 25 MHz search unit

A

a. A 1 MHz search unit

Note: Lower frequecy the thicker the crystal

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21
Q

The amount of energy reflected from a discointinuity will be dependent on:

a. The size of the discontinuity
b. The orientation of the discontinuty
c. The type of the discontinuity
d. All of the above

A

d. All of the above

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22
Q

Which of the following can occur when an ultrasonic beam reaches the interface of two dissimilar materials?

a Reflection

b. Refraction
c. Mode conversion
d. All of the above

A

d. All of the above

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23
Q

The phenomenon by which a wave strikes a boundary and changes the direction of its propagation is referred to as:

a. Divergence
b. Rarefaction
c. Angulation
d. Reflection

A

d. Reflection

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24
Q

Which of the following is the correct formula for determining near field?

a. NF = D^2 F/ 4V
b. NF = D^2V/4F
c. NF = 4V/D^2F
d. NF = 4F/ D^2 V

A

a. NF = D^2 F/ 4V

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25
Q

The near field effects of a contact transducer may be reduced by:

a. Increasing transducer frequency
b. use of smaller diameter transducer
c. using an apprpriate water path
d. use of a focused transducer

A

b. use of smaller diameter transducer

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26
Q

Calculate the near field of a 2.25 MHz., 12 mm diameter transducer used on a steel test piece that has a velocity of 5.90 km/sec.

a. 1.14 mm
b. 2.57 mm
c. 13.72 mm
d. 54.9mm

A

c. 13.72 mm

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27
Q

The angle at which 90 degree refraction of a shear wave is reached is called:

a. The angle of incidence
b. The first citical angle
c. The angle of maximum reflection
d. The second critical angle

A

d. The second critical angle

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28
Q

Where does the beam divergence occur?

a. In the near field
b. At the boundary of the near field and far field
c. at the face of the crystal
d. None of the above

A

b. At the boundary of the near field and far field

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29
Q

Which of the following is the correct formula for determining beam divergence:

a. sinØ = 1.22V/Df
b. sinØ= 1.22Df / V
c. cosØ = 1.22V / Df
d. tanØ = 1.22V / Df

A

a. sinØ= 1.22V/Df

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30
Q

Which of the following is the correct formula for wavelength?

a. Wavelength = Frequency / Velocity
b. Wavelength = Velocity X Frequency
c. Wavelength = Velocity / Frequency
d. Wavelength = Velocity + Frequency

A

c. Wavelength = Velocity / Frequency

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31
Q

Inspection of castings is often impractical because of :

a. extremely small grain structure
b. coarse grain structure
c. uniform flow lines
d. uniform velocity of sound

A

b. Coarse grain structure

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32
Q

Calculate the near field length for a transducer 12 mm in diameter, 2.5 Mhz, in a medium with a velocity of 6.0 km/s

a. 15.0 mm
b. 1.25 mm
c. 12.5 mm
d. 1.5 mm

A

a. 15.0 mm

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33
Q

The formula for acoustic impedance is :

a. Z= p - V
b. Z= P/V
c. Z= p X V
d. Z= p + V

A

c. Z= p X V

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34
Q

The angle at which 90 degree reraction of a longitudinal sound wave is reached is called:

a. The angle of Incidence
b. The first critical angle
c. The angle of maximum reflection
d. The second critical Angle

A

b. The First Critical angle

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35
Q

What is the angle of a plastic shoe to get the 1st critical angle in brass?

a. 54.8 Degrees
b. 75.7 Degrees
c. 65,4 Degrees
d. 37.2

A

37.2

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36
Q

A plastic shoe with an angle of 35 degrees produces a shear wave an angle of _____________ in steel?

a. 24 degrees
b. 44 degrees
c. 1.25 degrees
d. 15 degrees

A

b. 44 degrees

sin35/2.67=sinØ2/3.23

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37
Q

An angle of 20 degrees in water produces a shear wave at an agle of ____ in steel?

a. 25.4 degrees
b. 18.8 degrees
c. 37.6 degrees
d. 1.35 degrees

A

c. 37.6 degrees

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38
Q

An incident longitudinal wave, transmitted at an angle less than the first critical angle will generate:

a. Longitudinal and shear waves
b. Longitudinal and surface waves
c. Longitudinal waves only
d. Shear waves only

A

a. Longitudinal and shear waves

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39
Q

Refracted sound waves are calculated using which of the following formulas:

a. Snells Law
b. Huygens Principle
c. Creeping wave formula
d. Acoustic Impedance

A

a. Snells law

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40
Q

Which of the following crystals is a good reciever of sound

a. Barium Titanate
b. Dilythium crystals
c. Lithium Sulphate
d. Iridium Kryonic

A

c. Lithium Sulphate

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41
Q

Which of the following is a good transmitter of sound

a. Barium Titanate
b. Dilthium crystals
c. Lithium Sulphate
d. Irridium Kryonic

A

a. Barium Titanate

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42
Q

The phenomenon by which a wave strikes a bounday and changes the direction of its propagation is referred to as:

a. Divergence
b. Rarefaction
c. Angulation
d. Reflection

A

D. Reflection

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43
Q

A frequency increases in ultrasonic testing, the angle of beam divergence of a given diameter crystal:

a. Decreases
b. Remains unchanged
c. Increases
d. Varies uniformly through each wavelength

A

a. Decreases

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44
Q

A second name for a compressional wave is :

a. Lamb wave
b. Shear wave
c. Longitudinal wave
d. Transverse wave

A

c. Longitudinal wave

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45
Q

An incident longitudinal wave, transmitted at an angle less than the first critical angle will generate:

a. Longitudinal and shear waves
b. Longitudinal and surface waves
c. longitudinal waves only
d. shear waves only

A

a. Longitudinal and shear waves

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46
Q

A material used between the face of a search unit and the test surface to permit or improve the transmission of ultrasonic vibrations from the search unit to the material being tested is called:

a. wetting agent
b. Couplant

C. acoustic transmitter

d. lubricant

A

b. Couplant

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47
Q

Which of the following provides aplan view of the item under examination and displays depth as different colors?

a. A-Scan presentation
b. B- Scan presentation
c. C-Scan presentation
d. none of the above are adaptable for printed outs

A

c. C-scan Presentation

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48
Q

Another name for a Rayleigh wave is:

A

Surface waves

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49
Q

Viscosity of couplant chosen for a contact ultrasonic inspection will usually depend on :

a. probe size
b. nominal frequency
c. surface condtion
d. sensitivity required

A

c. Surface Condition

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50
Q

The indication on the display screen which represents the far boundary of the material being tested is called:

a. hash
b. the initial pulse
c. the “Main bang”
d. the back reflection

A

c. The Back Reflection

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51
Q

The critical angle refers to the

a. longitudinal waves angle
b. incident angle
c. refracted angle
d. reflected shear wave

A

b. Incident angle

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52
Q

Defects near the entry surface cannot always be accurately due to:

a. far-field effect
b. attenuation
c. test system recovery time ( Near Field)
d. Refraction

A

c. Test system recovery time ( Near Field)

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53
Q

Which of the following can occur when an ultrasonic beam reaches the interface of two dissimilar materials?

a, Reflection

b. Refraction
c. Mode conversion
d. All of the above

A

d. All of the above

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54
Q

Most commercial ultrasonic testing is accomplished using frequencies between:

a. 1-25 kHz
b. 1- 25 MHz
c. 1 -1000 kHz
d. 15- 100MHz

A

b. 1-25 MHz

55
Q

A term used in ultrasonics to express the speed at which sound waves pass through various substances is:

a. Frequency
b. Velocity
c. Wave length
d. None of the above

A

b. Velocity

56
Q

When an ultrasonic beam passes through the interface of two dissimiilar materials at an angle a new angle of sound travel takes place in the second material due to:

a. Attenuation
b. Rarefractionm
c. Compression
d. Refraction

A

d. Refraction

57
Q

Which of the following frequencies would probably result in the greatest ultrasonic attenuation losses?

a. 5.0 MHz
b. 2.25 MHz
c. 10 MHz
d. 25 MHz

A

d. 25 MHz

58
Q

The reference holes in standard aluminum area-amplitude ultrasonic test blocks contain:

a. Flat-bottom refference holes
b. Concave reference holes
c. Convex reference holes
d. Conical shaped reference holes

A

a. Flat- bottom refference holes

59
Q

In which medium listed below would the velocity of sound be the lowest?

a. Air
b. Water
c. Aluminum
d. Stainless Steel

A

a. Air

60
Q

The angular position of the reflecting surface of a discontinuity with respect to the entry surface is referred to as:

a. The angle of incidence
b. The angle of refraction
c. The orientation of the discontinuity
d. None of the above

A

c.The orientation of the discontinuity

61
Q

The near field effects of a contact transduer may be reduced by:

a. Decreasing transducer frequency
b. Use of larger diameter transducer
c. using an appropriate water path
d. use of a focused transducer

A

a. decreasing transducer freqquency

62
Q

Compresssion-rarefaction waves whose particle displacement is parallel to the direction of propagation are called:

a. Longitudinal waves
b. Shear waves
c. Lamb waves
d. Rayleigh waves

A

a. Longitudinal waves

63
Q

Mechanical wave motion requires:

a. High Pressure
b. Low Pressure
c. Particle Motion
d. Ionic Bonding and disbonding

A

c. Particle Motion

64
Q

Waves used in ultrasonic testing of materials are _______ in nature.

a. Mechanical
b. Magnetic
c. Electromagnetic
d. Harmonious

A

a. Mechanical

65
Q

In a longitudinal wave, zones of compression alternate with _____ zones.

a. Dead
b. Rarified
c. Subduction
d. Anticline

A

b. Rarified

66
Q

Elastic waves can be transmitted in

a. Air
b. Water
c. Solids
d. All of the above

A

d. All of the above

67
Q

The smallest distance between two points on an elastic wave where the particles are in the same state of motion is the

a. Period
b. Wavelength
c. Frequency
d. Hypotenuse

A

b. Wavelength

68
Q

The maximum displacement of a particle from its point of rest in a sound wave is its

a. Velocity
b. Amplitude of movement
c. Frequency
d. Wavelength

A

b. Amplitude of movement

69
Q

Particle motion in a longitudinal wave is

a. Parallel to the direction of wave propagation
b. At right angles to the direction of wave propagation
c. Retrograde
d. In counterclockwise ellipses

A

a. Parallel to the direction of wave progation

70
Q

In transverse waves, particle motion is…

a. Parallel to the direction of wave propagation
b. Right angles to the direction of wave propagation
c. Retrograde
d. In counterclockwies ellipses

A

b. Right angles to the direction of wave propagation

71
Q

Rayleigh waves are a phenomenon assoicated with

a. Solid to liquid boundaries
b. Solid to air boundaries
c. Solid to solid boundaries
d. All of the above

A

d. All of the above

72
Q

Surface waves limited on two surfaces are also called

a. Longitudinal Waves
b. Lamb waves
c. Shear waves
d. P waves

A

B. Lamb Waves

73
Q

Rayleigh, shear and longitudinal describe

a. Wave forms
b. Wave modes
c. Wave lengths
d. Wave guides

A

b. Wave Modes

74
Q

In general, the result of two waves interacting on each other can be found by

a. Strobe lighting
b. Vector addition
c. Cross-multiplying
d. Linear summation

A

b. Vector addition

75
Q

The point where no particle displacement occurs on a standing wave is called

a. An Anticline
b. An Antinode
c. A Node
d. A Dead Zone

A

c. A Node

76
Q

The point were maximum particle displacement occurs on a standing wave is called

a. an Anticline
b. an Antinode
c. a Node
d. a Peak Detector

A

b. an Antinode

77
Q

Wavelength of sound is determined by

a. (Velocity) / (Frequency)
b. (Frequency) / (Velocity)
c. (Frequency) X (Velocity)
d. None of the above

A

A, (Velocity) / (Frequency)

78
Q

Compared to water, the acoustic impedance of steel is

a. Higher
b. Lower
c. About the same
d. Higher or lower depending on the wave mode

A

a. Higher

79
Q

2,500,000 cyles per second (cps) is also expressed as

a. 25kHz
b. 2.5 MHz
c. 2.5 mHz
d. 25 GHz

A

b. 2.5 MHz

80
Q

The product of acoustic velocity times the density of a material gives

a. Power Intensity
b. Frequency
c. Wavelength
d. Acoustic Impedance

A

d. Acoustic Impedance

81
Q

In steel, shear wave velocity as compared to longitudinal wave velocity is about

a. Twice as fast
b. The same
c. One half as fast
d. One quarter as fast

A

c. One half as fast

82
Q

The usual form of denoting acoustic impedance is

a. Z
b. A
c. I
r. R

A

a. Z

83
Q

If a material borders on empty space the interface is called

a. A Vaccum
b. Infinity
c. A Free Boundary
d. None of the above

A

c. A Free Boundary

84
Q

In determining the coefficient of reflection, a negative value indicates

a. Reduced amplitude
b. Loss of sound pressure
c. Phase reversal relative to the incident wave
d. None of the above

A

c. Phase reversal relative to the incident wave

85
Q

Phase reversal of an ultrasound wave upon reflection from a sonically softer material is indicated by

a. a zero R value
b. a negative R value
c. an R value greater than 1
d. increased resonance

A

b. a negative R value

86
Q

Incidence of a sound wave from a solid to a gas is considered a free boundary condition because

a. There are no particles in a gas
b. All sound is lost in transmission
c. The acoustic impedance of a gas is essentially zero
d. none of the above

A

C. The acoustic impedance of a gas is essentially zero

87
Q

Bending of a sound wave upon entering a new medium is explained by

a. Krautkramer’s Law
b. Snell’s Law
c. Boyle’s Law
d. Hooke’s Law

A

b. Snell’s Law

88
Q

If a sound beam is incident on steel from water at 20 degrees, the refracted transverse wave will have an angle

a. Greater than 20 degrees
b. Less than 20 degrees
c. About 20 degrees
d. That cannot be determined

A

a. Greater than 20 degrees

89
Q

The change from longitudinal to transverse waves (and visa versa) at a boundary is called

a. Snell’s Law
b. Mode conversion
c. Reciprocity
d. Reversal

A

b. Mode Conversion

90
Q

The incident angle at which the transmitted longitudinal wave first ceases to exist in the diffracting medium is called the

a. Longitudinal angle
b. Short angle
c. First critical angle
d. Second critical angle

A

c. First critical angle

91
Q

The incident angle at which the transmitted transverse wave first ceases to exist in the refracting medium is called the

a. Long angle
b. Short angle
c. First critical angle
d. Second critical angle

A

d. Second critical angle

92
Q

The critical angle for the longitudinal wave is also called the

a. Right angle
b. Snell angle
c. First critical angle
d. Second critical angle

A

c. First critical angle

93
Q

The critical angle for the transverse wave is also called the

a. Right Angle
b. Snell Angle
c. First Critical Angle
d. Second Critical Angle

A

d. Second Critical Angle

94
Q

Mode conversion in ultrasonics occurs at

a. Defects
b. Corner Reflectors
c. Only Free Boundaries
d. All Boundaries

A

d. All Boundaries

95
Q

For a longitudinal wave entering a medium of lower acoustic velocity, the refracted longitudinal wave angle in the new material will be

a. Totally internally reflected
b. The same
c. Less than incidence angle
d. Greater than incidence angle

A

c. Less than incidence angle

96
Q

The law of reflection requires that

a. The angle of reflection equals the angle of incidence
b. The normal to the reflecting surface, the reflected ray
c. both a and b
d. none of the above

A

c. Both a and b

97
Q

The “Bending” of sound waves at gaps and openings is accounted for by

a. Reflection
b. Difffraction
c. Density
d. Acoustic Pressure

A

b. Diffraction

98
Q

The length of a particular sound wave that is measured from trough to trough, or from crest to crest will always be the same.

What is this distance known as?

A

Wavelength

99
Q

Wavelength is often expressed in_____

V is Velocity of sound expressed in _____

F is the Frequency of the wave expressed in _____

A

Wavelength expressed in Milimeters

Veolcity expressed in Kilometers

Frequency expressed in Megahertz

100
Q

Qualification is :

A

A process that should take place before a person can become certified.

101
Q

The maximum displacement of a particle from its point of rest in a sound wave is its

a) Velocity
b) Amplitude of movement
c) Frequency
d) Wavelength

A

b) Amplitude of movement

102
Q

Rayleigh waves are a phenomenon associated with

a) solid to liquid boundaries
b) solid to air boundaries
c) solid to solid boundaries
d) all of the above

A

d) All of the above

103
Q

Surface waves limited on two surfaces are also called

a) long. waves
b) lamp waves
c) shear waves
d) P waves

A

b) Lamp Waves

104
Q

Rayleigh, Shear and Longitudinal describe

a) wave forms
b) wave modes
c) wave lengths
d) wave guides

A

b) wave modes

105
Q

In general the result of two waves interacting on each others can e found by

a) strobe lighting
b) vetor addition
c) cross-multiplying
d) linear summation

A

b) Vector addition

106
Q

The point where noparticle displacement occurs on a standing wave is called

a) an anticline
b) an antinode
c) a node
d) a dead zone

A

c) a node

107
Q

The point where maximum particle displacement occurs on a standing wave is called

a) an anticline
b) antinode
c) a node
d) a peak detector

A

b) antinode

108
Q

If a material borders on empty space the interface is called

a) a vacum
b) infinity
c) a free boundary
d) none of the above

A

c) a free boundary

109
Q

In determining the coefficient of reflection, a negative value indicates

a) reduced amplitude
b) loss of sound pressure
c) phase reversal relative to the incident wave
d) none of the above

A

c) phase reversal realative to the incident wave

110
Q

Phase reversal of an ultasound wave upon reflection from a sonically softer material is indicated by

a) a zero R value
b) a negative R value
c) an R value greater than 1
d) increased resonance

A

b) a begative R value

111
Q

Incidence of a sound wave from a solid to a gas is considered a free boundary condition because

a) there are no particles in a gas
b) all sound is lost in transmission
c) the acoustic impedance of a gas is essentially zero
d) none of the above

A

c) the acoustic impedance of a gas is essentially zero

112
Q

Bending of a sound wave upon entering a new medium is explained by

a) Krautkramer’s law
b) Snell’s law
c) Boyle’s law
d) Hooke’s law

A

b) Snell’s law

113
Q

The incident angle at which the transmitted longitudinal wave first ceases to exist in the defracting medium is called the

a) longitudinal angle
b) short angle
c) first critcal angle
d) second critical angle

A

c) first critical angle

114
Q

Mode conversion in ultrasonics occurs at

a) defects
b) corner reflectors
c) only free boundaries
d) all boundaries

A

d) All boundaies

115
Q

For a longitudinal wave entering a medium of lower acoustic velocity, the refracted longitudinal wave angle in the new material will be

a) totally internally reflected
b) the same
c) less than incidence angle
d) greater than incidence angle

A

c) less than incidence angle

116
Q

The law of reflection requires that

a) the angle of reflection equals the angle of incidence
b) the normal to the reflections surface, the reflected ray and incident ray lie in the same place
c) both a and b
d) none of the above

A

c) both a and b

117
Q

The “bending” of sound waves at gaps and openings is accounted for by

a) reflection
b) diffraction
c) density
d) acoustic pressure

A

b) Diffraction

118
Q

According to germetric-optic treatment of sound, acoustic pressure

a) increases with distance from source
b) decreases with distance from source
c) varies unpredictably with distance from source
d) none of the above

A

b) decreases with distance from source

119
Q

Reflection and refraction phenomenon are illustrated in geometric-optic treatment of ultrasound by means of

a) mirrors
b) equations
c) rays and straight lines
d) none of the above

A

c) rays and straight lines

120
Q

In practical ultrasonic testing, mirror surfaces can be used with sound beams to

a) image flaws
b) reach points of difficult access
c) reduce scatter
d) reduce short wave dispersion effects

A

b) reach points of difficult access

121
Q

The interference pattern produced in front of a transducer face is a result of

a) rarefraction
b) dispersion
c) diffraction
d) refraction

A

c) diffraction

122
Q

The distance from the probe face to the last maximum on the beam axis is called the

a) near field
b) far field
c) dead zone
d) ozone

A

a) near field

123
Q

Acoustic pressure fluctuates in the near zone due to

a) diffraction interference
b) dispersion
c) refraction
d) density fluctuations

A

a) diffraction interference

124
Q

A longitudinal wave generating transducer will have a given near field in steel. If in water the near field for this probe will be

a) the same distance
b) about half as long
c) about 1/4 as long
d) about 4 times as long

A

d) about 4 times as long

125
Q

Beyond the near zone of an ultrasound beam from a probe is the

a) dead zone
b) Fresnel zone
c) Far field
d) null zone

A

c) Far Field

126
Q

Variations in acoustic pressure at the right angles to the probes’ sound beam in the near zone are a result of

a) side lobes
b) overtones
c) sub harmonics
d) divergence

A

a) Side lobes

127
Q

The angle of divergence is

a. Constant for a given piezoelectic material
b. Applicable to the far zone only
c. Increases with increasing probe dimensions
d. Decreases with increasing wavelength

A

b. Applicable to the far zone only

128
Q

The “main lobe” of a rectangular probe is

a. Axially symmetric
b. Broader in the small probe dimension
c. Narrower in the small probe dimension
d. Two Dimensional

A

b. Boader in the small probe dimension

129
Q

Focusing of ultrasound is accomplished by

a. Curved piezelectric crystals
b. Lenses
c. Both a and b
d. none of the above

A

c. Both a and b

130
Q

Difficulties determining exact lateral location and relative size of a flat reflector in the near zone results from

a. The dead zone
b. Ring down
c. Multiple maxima and minima
d. Absorption

A
131
Q

AVG (or DGS in English ) diagrams are used for

a. Establishing gain settings
b. Determining vertical beam spreads
c. Estimating flaw size
d. None of the above

A

c. Estimating flaw size

132
Q

Flaw detection using the through transmission method can give accurate information about

a. Flaw depth
b. Flaw type
c. Flaw orientation

D. None of the above

A

d. None of the above

133
Q

In Ultrasonic testing, a wave pulse contains

a. A single well defined frequencyu
b. A range of frequencies
c. Two full cycles
d. Only positive going waves

A

b. A range of frequencies