Ut Lvl 1

Question 1

The main advantage of the Rompas or DIN block (IIW block 2) is

a) increased number of characteristics that can be tested
b) greater ranges can be tested
c) improved sensitivity calibrations
d) portability

Answer 1

d) portability

Question 2

In ultrasonic testing, one of the best means of conveying a large quantity of information about a test piece is by

a) B-scans
b) C-scans
c) ultrasonic imaging
d) the tandem probe technique

Answer 2

c) ultrasonic imaging

Question 3

Decreased damping on a piezoelectric element results in

a) reduced ringing time
b) increased resolution
c) decreased sensitivity
d) all of the above

Answer 3

d) all of the above

Question 4

Information obtained about the exit point and refracted angle of an angle beam probe

a) is qualitative only
b) must be check periodically since the probe is subject to wear
c) is fixed by the manufacture
d) none of the above

Answer 4

b) must be check periodically since the probe is subject to wear

Question 5

When a piezoelectric material has a voltage applied to it

a) eddy currents are generated
b) flux leakage can be used for testing
c) mechanical deformation occurs
d) all of the above

Answer 5

c) mechanical deformation occurs

Question 6

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

Answer 6

b) reach points of difficult access

Question 7

The usual form of denoting acoustic impedance is

a) Z
b) A
c) I
d) R

Answer 7

a) Z

Question 8

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

a) the dead zone
b) ring down
c) multiple maxima and minima
d) absorption

Answer 8

c) multiple maxima and minima

Question 9

Focusing of ultrasound is accomplished by

a) curved piezoelectric crystals
b) lenses
c) both a and b
d) none of the above

Answer 9

c) both a and b

Question 10

If the beam from an unfocused probe strikes a convex steel surface from water with normal incidence it will

a) increase beam spread
b) decrease beam spread
c) focus the beam
d) none of the above

Answer 10

a) increase beam spread

Question 11

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

Answer 11

c) first critical angle

Question 12

When using angle beams (transverse waves) for ultrasonic testing, the position of a flaw signal on the timebase can be
calibrated for

a) sound path length
b) stand-off distance
c) depth of defect
d) all of the above

Answer 12

d) all of the above

Question 13

Mode conversion in ultrasonics occurs at

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

Answer 13

d) all boundaries

Question 14

Attenuation is not a result of

a) beam geometry
b) scatter
c) bond breaking at the molecular level
d) absorption

Answer 14

a) beam geometry

Question 15

In ultrasonic testing, a wave pulse contains

a) a single well defined frequency
b) a range of frequencies
c) two full cycles
d) only positive going waves

Answer 15

b) a range of frequencies

Question 16

In an A-scan presentation, the indication of the instant at which the pulse is applied to the transmitting crystal is the ________
indication.

a) initial pulse
b) threshold
c) R-F
d) sweep

Answer 16

a) initial pulse

Question 17

To avoid distortion of received ultrasonic signals the receiver amplifier should have similar bandwidth characteristics as the

a) test piece resonant frequency
b) receiving transducer
c) transmitting transducer
d) none of the above, receiver bandwidth is not important

Answer 17

b) receiving transducer

Question 18

The IIW block is used primarily

a) for contact probes
b) for angle beam probes
c) for immersion work
d) in place of the IOW block

Answer 18

a) for contact probes

Question 19

In plate testing with angle beams, the full skip distance refers to

a) the sound path to the opposite wall
b) twice the sound path to the opposite wall
c) the plate thickness
d) twice the plate thickness

Answer 19

b) twice the sound path to the opposite wall

Question 20

Variations in acoustic pressure at 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

Answer 20

a) side lobes

Question 21

Severity of a defect is determined by

a) amplitude of signal relative to reference
b) length of flaw
c) type and orientation of flaw
d) all of the above

Answer 21

d) all of the above

Question 22

Which of the following methods would not use pulsed ultrasound?

a) pulse-echo
b) pitch-catch
c) through-transmissions
d) all of the above would use pulse ultrasound

Answer 22

d) all of the above would use pulse ultrasound

Question 23

The advantage of magnetrostrictive transducers is

a) sturdiness
b) resistance to damage under adverse conditions
c) ability to be constructed in very large sizes
d) all of the above

Answer 23

d) all of the above

Question 24

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

Answer 24

d) none of the above

Question 25

When drawing a distance/amplitude curve (DAC) you set the signal from the reference hole which gives the maximum
amplitude to

a) 100% full screen height (FSH)
b) 80% - 90% FSH
c) 50% FSH
d) 12 dB over the response from the 7/8 node

Answer 25

b) 80% - 90% FSH

Question 26

Wavelength of sound is determined by

a) (velocity) / (frequency)
b) (frequency) / (velocity)
c) (frequency) X (velocity)
d) none of the above

Answer 26

a) (velocity) / (frequency)

Question 27

The plastic prism coupled between and ultrasonic transducer and a test piece which causes the ultrasonic waves to propagate
at a known angle within the test piece is called a

a) wedge
b) solid couplant
c) variable angle adapter
d) none of the above

Answer 27

a) wedge

Question 28

Manual probe movement in contact scanning to evaluate a defect for type is

a) in the lateral direction
b) in a transversing direction
c) both orbital and rotational
d) always a combination of all of the above

Answer 28

d) always a combination of all of the above

Question 29

Mechanical deformation of a material placed in a magnetic field is called

a) magnetostriction
b) warp factor
c) reverse piezoelectric effect
d) undulation

Answer 29

a) magnetostriction

Question 30

To improve the accuracy of defect location and evaluation you should

a) reduce gain
b) increase range
c) check calibration
d) use a probe of higher frequency

Answer 30

c) check calibration

Question 31

Most codes would recommend the actual beam angle of an angle beam probe not deviate from the indicated angle by more than

a) one half degree
b) one degree
c) two degrees
d) five degrees

Answer 31

c) two degrees

Question 32

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

a) mechanical
b) magnetic
c) electromagnetic
d) harmonious

Answer 32

a) mechanical

Question 33

The result of a rough test surface in ultrasonic testing is

a) reduced acoustic coupling
b) beam distortion
c) to change the wavelength of sound in the test piece
d) both a and b

Answer 33

d) both a and b

Question 34

A rough surface may affect resolution and sensitivity by

a) increasing scatter
b) causing unwanted mode conversions
c) decreasing coupling
d) all of the above

Answer 34

d) all of the above

Question 35

Acoustic pressure along the beam axis moving away from the probe has various maxma and minima due to interference. At
the end of the near field pressure is

a) a maximum
b) a minimum
c) the average of all maxima and minima
d) none of the above

Answer 35

a) a maximum

Question 36

Which mode of wave used in nondestructive testing is not initially produced by mode conversion?

a) longitudinal
b) shear
c) transverse
d) Rayleligh

Answer 36

a) longitudinal

Question 37

Surface waves limited on two surfaces are also called

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

Answer 37

b) lamb waves

Question 38

Which is not a commonly used target when establishing sensitivity for ultrasonic testing?

a) side drilled holes
b) a tungsten ball
c) the 100 mm quadrant of the IIW block
d) flat bottom holes

Answer 38

b) a tungsten ball

Question 39

A focused probe is positioned in water 5 cm over a plate 10cm thick. The probe having a focal length of 6 cm will focus

a) 1 cm above the plate
b) 0.25 cm from the entry surface of the plate
c) 0.25 cm from the back surface of the plate
d) 0.4 cm into the water on the opposite side of the plate

Answer 39

b) 0.25 cm from the entry surface of the plate

Question 40

Most piezoelectric ceramics (ferroelectrics) are

a) polycrystalline
b) also ferromagnetic
c) statically charged
d) are better receivers than transmitters

Answer 40

b) also ferromagnetic

Question 41

The method whereby sound is transmitted through a plate from a transmitter on one side to a receiver on the other

a) is used to characterize flaws
b) is called an intensity method
c) is used to determine flaw depth
d) all of the above

Answer 41

b) is called an intensity method

Question 42

Significant advantage of ultrasonics over radiography is

a) it is safe
b) it can be used on ferrous and non-ferrous metals
c) all defects in any piece can be located
d) the ability to use it underwater

Answer 42

a) it is safe

Question 43

Scatter is more likely to be a problem if

a) grain size is small
b) grain size is large
c) a material is isotropic
d) grain crystals are cubic

Answer 43

b) grain size is large

Question 44

When contact testing is performed, a transfer value is

a) used to compensate for attenuation
b) used to compensate for variations in coupling
c) both a and b
d) not used

Answer 44

c) both a and b

Question 45

Methods of generating and receiving ultrasound by deformation of ferromagnetic materials in a magnetic field utilize the phenomenon called

a) magnetics
b) electrodynamics
c) magnetostriction
d) eddy currents

Answer 45

c) magnetostriction

Question 46

In addition to a low critical temperature, lithium sulphate hydrate

a) is soluble in water so must be water proofed
b) is a poor impedance match to water
c) has the lowest coupling coefficient
d) none of the above

Answer 46

a) is soluble in water so must be water proofed

Question 47

When using quartz as a piezoelectric transducer, longitudinal waves are generated from the

a) X - cut
b) Y - cut
c) Z - cut
d) GT - cut

Answer 47

a) X - cut

Question 48

Flat bottom hole test blocks are made

a) of the same alloy as the test piece
b) with varying depth from the test surface to compare response at different distances from the probe
c) with different target sizes to establish reflection equality between a flaw and a standard
d) all of the above

Answer 48

d) all of the above

Question 49

Pulse length determines a probes’

a) frequency
b) acoustic impedance
c) damping
d) depth resolution

Answer 49

d) depth resolution

Question 50

The dominant frequency of an ultrasonic flaw detection system depends on the

a) probe
b) machine receiver and amplifier
c) pulse propagation path
d) all of the above

Answer 50

d) all of the above

Question 51

The effect of increasing the temperature of a test piece to 30 degrees C. is to

a) improve acoustic coupling
b) decrease resolution
c) require high temperature couplant
d) decrease acoustic velocity

Answer 51

d) decrease acoustic velocity

Question 52

If a signal is reduced from 84% to 42% FSH, the number of dB gain removed from the receiver is

a) 2
b) 6
c) 12
d) 42

Answer 52

b) 6

Question 53

Although quartz has about twice the receiving sensitivity of PZT, PZT used for pulse-echo testing in NDT results in higher
amplitude signals for the same conditions because

a) transmission constant is higher
b) PZT dielectric constant is lower
c) PZT has a lower density
d) all of the above

Answer 53

a) transmission constant is higher

Question 54

Spreading the timebase interval to enable signals from a selected range to be displayed is called

a) magnification
b) delay
c) scale expansion
d) decompression

Answer 54

c) scale expansion

Question 55

A large Q factor indicates

a) high damping
b) narrow bandwidth
c) wide bandwidth
d) low permeability

Answer 55

b) narrow bandwidth

Question 56

More scatter of a sound beam is had when using

a) high PRF
b) short pulse lengths
c) higher frequency probes
d) lucite delay lines

Answer 56

c) higher frequency probes

Question 57

Resonance testing methods are used for

a) determining Poisson’s ratio
b) flaw detection
c) thickness testing
d) all of the above

Answer 57

c) thickness testing

Question 58

When performing contact angle beam testing interferring surface waves can be distinguished from flaws by

a) triangulation
b) testing from the opposite side
c) touching the work surface with an oily finger
d) none of the above

Answer 58

c) touching the work surface with an oily finger

Question 59

A property of the receiver amplifier that is periodically verified is

a) horizontal linearity
b) vertical linearity
c) beam spread
d) near zone

Answer 59

b) vertical linearity

Question 60

Unless otherwise noted, the refracted beam angle on a perspex wedge is the refracted angle in

a) aluminum
b) brass
c) plastic
d) steel

Answer 60

d) steel

Question 61

Thickness measurements of plates are made using ______ waves.

a) Rayleigh
b) shear
c) compressional
d) Lamb

Answer 61

c) compressional

Question 62

A calibration block can be used to

a) check instrument and probe characteristics
b) set sensitivity for inspection
c) reproduce previously used settings
d) all of the above

Answer 62

d) all of the above

Question 63

The position of a defect found by an angle beam inspection requires that you know

a) the refracted angle and exit point
b) sound path distance
c) geometry and dimensions of the test piece
d) all of the above must be known

Answer 63

d) all of the above must be known

Question 64

The number of oscillations per second experienced by a particle as an acoustic wave passes through it is called the

a) wavelength of the oscillation
b) acoustic frequency
c) period of oscillation
d) none of the above

Answer 64

b) acoustic frequency

Question 65

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

Answer 65

c) estimating flaw size

Question 66

Lithium sulphate as a transducer material is most notable for its

a) high curie point
b) low coupling coefficient
c) high solubility in water
d) none of the above, lithium sulphate is not used as a transducer material

Answer 66

c) high solubility in water

Question 67

In ultrasonic spectrum analysis, the effect of increasing metal grain size on the spectra would be

a) reduction in lower frequencies
b) reduction in higher frequencies
c) an increase in frequencies at the corresponding grain size
d) none of the above

Answer 67

b) reduction in higher frequencies

Question 68

Generally, longitudinal waves propagate__________.

a) faster than shear waves
b) slower than shear waves
c) at right angles to shear waves
d) parallel to shear waves

Answer 68

a) faster than shear waves

Question 69

For an ultrasound beam to skip in the circumferential direction of a tubular product

a) the ratio of inside to outside diameter must be right
b) the incident angle must be sufficiently steep
c) both a and b
d) none of the above

Answer 69

c) both a and b

Question 70

The most common single measurement made on ultrasonic transducers is determination of

a) nature of sound field
b) bandwidth
c) actual centre frequency
d) none of the above

Answer 70

a) nature of sound field

Question 71

Surface wave ultrasonic testing is superior to penetrant testing because it

a) is cheaper
b) is faster
c) can find sub-surface defects
d) can be used on ferro-magnetic materials

Answer 71

c) can find sub-surface defects

Question 72

The purpose of highly absorptive backing material in transducers used for testing is to

a) eliminate sound re-entering the crystal
b) maximize rise time
c) maximize fall time
d) obtain highest resolution by broadening the frequency bandwidth

Answer 72

a) eliminate sound re-entering the crystal

Question 73

When performing a pulse-echo test, if you scanned over a large defect with the same acoustic impedance as the material you were testing

a) maximum response would occur only at right angles
b) the AVG (DGS) method would be used for sizing
c) it would not be detected
d) detection would depend on how much gain over reference you were scanning with

Answer 73

c) it would not be detected

Question 74

Short highly damped pulses of ultrasound have their advantage in NDT in that

a) sensitivity is increased
b) time measurement accuracy is improved
c) defect characterizations is simplified
d) all of the above

Answer 74

b) time measurement accuracy is improved

Question 75

A deviation in actual refracted angle of + or - 2 degrees will result in

a) errors in depth calculations
b) errors in stand-off calculations
c) errors in sound path calculations
d) both a and b

Answer 75

d) both a and b

Question 76

The principles involved in testing non-metals by ultrasonics as compared to metals are

a) significantly different with regards to coupling only
b) simpler because shear waves are not involved
c) more complex due to birefringence
d) essentially the same

Answer 76

d) essentially the same

Question 77

The best way to determine the required sensitivity for ultrasonic testing is

a) to use 20 dB over the gain needed to put the 1.5 mm diameter hole of the IIW block to 80% FSH
b) use enough gain to get “10% grass” from the opposite wall
c) use reference welds with real defects of the minimum acceptable size
d) from flat bottom hole and side drilled hole response studies

Answer 77

c) use reference welds with real defects of the minimum acceptable size

Question 78

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

Answer 78

d) second critical angle

Question 79

If a 1 MHz quartz crystal (cut for half-wave resonance) is 0.29 cm thick, how thick would it have to be if the half-wave resonance frequency was to be 10 MHz?

a) 0.29 mm
b) 2.9 mm
c) 2.9 cm
d) 5.8 microns

Answer 79

a) 0.29 mm

Question 80

In ultrasonic testing a piezoelectric material is used to

a) convert electric energy to mechanical energy
b) convert mechanical energy to electrical energy
c) both a and b
d) none of the above

Answer 80

c) both a and b

Question 81

When performing contact ultrasonic testing, significant amplitude variations from the same indication can result from

a) transducer angle
b) couplant thickness
c) probe wear face thickness
d) all of the above

Answer 81

d) all of the above

Question 82

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

Answer 82

a) parallel to the direction of wave propagation

Question 83

In some ultrasonic probe arrangements, one variety of piezo material is used for the transmitter and another for the receiver. The purpose of two different materials is

a) to make fabrication of the probe easier
b) to take advantage of broadband receivers
c) to optimise relative efficiencies of transmitter and receiver elements
d) all of the above

Answer 83

c) to optimise relative efficiencies of transmitter and receiver elements

Question 84

The phenomenon whereby a longitudinal wave generates waves of other modes upon reflection or refraction is

a) total internal reflection
b) mode conversion
c) conversion mechanics
d) none of the above

Answer 84

b) mode conversion

Question 85

The amount by which the electrical signal from the ultrasonic transducer is amplified is

a) the gain
b) signal-to-noise ratio
c) 6
d) none of the above

Answer 85

a) the gain

Question 86

The purpose of water jets in ultrasonic inspection of hot plate (100°C.) is

a) to provide a coupling medium
b) to keep the probe cool
c) both a and b
d) none of the above

Answer 86

c) both a and b

Question 87

When a longitudinal wave is directed along the length of a large solid shaft from an end of the shaft, sensitivity to defects fluctuates as the probe is moved from the centre to the outside edge of the shaft. This is accounted for by

a) interfering edge effects
b) the near zone
c) mode conversion
d) none of the above

Answer 87

a) interfering edge effects

Question 88

Higher frequency probes are not preferred for inspection of castings due to

a) poor directivity
b) higher coefficients of transmission
c) higher coefficients of reflection
d) scatter

Answer 88

d) scatter

Question 89

If not equipped with a frequency selector for the receiver amplifier an ultrasonic machine would probably use a (an)

a) broadband receiver
b) wide receiver
c) ineligible receiver
d) tight end

Answer 89

a) broadband receiver

Question 90

Shifts of the positive charge on the silicon and negative charge on the oxygen in a quartz crystals account for

a) twin crystals
b) the piezoelectric effect
c) polymorphs
d) none of the above

Answer 90

b) the piezoelectric effect

Question 91

The method of non-destructive testing which uses acoustic energy usually in the 1MHz to 5 MHz range is

a) sub-sonic testing
b) ultrasonic testing
c) E-M testing
d) acoustic flux leakage testing

Answer 91

b) ultrasonic testing

Question 92

The purpose of moving a contact angle beam probe back and forth perpendicular to the axis of the weld inspected is to

a) evaluate defects
b) eliminate the need for scanning from 2 sides
c) ensure full volumetric inspection of weld and heat affected zone
d) practice echo-dynamics

Answer 92

c) ensure full volumetric inspection of weld and heat affected zone

Question 93

When ferro electric ceramics such as PZT are heated to above their curie point and held under a bias voltage while cooling to 80øC they are considered

a) neutralized
b) annealed
c) poled or polarized
d) charged

Answer 93

c) poled or polarized

Question 94

For a plane wave, sound pressure is reduced by attenuation in a _______ fashion.

a) linear
b) exponential
c) random
d) none of the above

Answer 94

b) exponential

Question 95

If a material borders on empty space the interface is called

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

Answer 95

c) a free boundary

Question 96

The testing of materials to detect internal, surface and concealed defects or discontinuities by methods which do not damage or destroy the material under test is called

a) surveillance testing
b) electromagnetic testing
c) acoustic testing
d) non-destructive testing

Answer 96

d) non-destructive testing

Question 97

The purpose of determining signal-to-noise ratio is

a) to verify good coupling
b) necessary to ensure small flaws do not go undetected
c) a check on the accuracy of the attenuator
d) a check on the sensitivity afforded by uncalibrated gain

Answer 97

b) necessary to ensure small flaws do not go undetected

Question 98

When using perspex wedges for contact testing, if the actual refracted angle varies by more than + or - 2 degrees the wedge
should be

a) replaced
b) re-ground
c) re-calibrated
d) a or b

Answer 98

d) a or b

Question 99

Modern ultrasonics uses signal processing methods like signal averaging, spectral analysis, deconvolution auto-correlation
and filtering to

a) increase scanning speeds of automated systems
b) eliminate ultrasonic operators
c) provide smoother looking A-scans
d) both locate and characterize flaws

Answer 99

d) both locate and characterize flaws

Question 100

Transducers with high-Q factor have

a) broadband-type pulses
b) poor penetrating ability
c) poor resolution compared to low-Q factor
d) all of the above

Answer 100

c) poor resolution compared to low-Q factor

Question 101

The delta technique uses

a) a single pulse echo probe
b) a transmitting probe and receiving probe on the same side of the test piece
c) a transmitting probe and receiving probe on opposite sides of the test piece
d) there is no such technique

Answer 101

b) a transmitting probe and receiving probe on the same side of the test piece

Question 102

The preferred presentation method for determining the amplitude of a echo signal is the

a) A-scan
b) B-scan
c) C-scan
d) D-scan

Answer 102

a) A-scan

Question 103

Ultrasonics used for drilling or machining has the advantage that

a) no cutting fluids are required
b) complex shapes can be cut out in a single pass
c) the workpiece does not heat up locally
d) all of the above

Answer 103

b) complex shapes can be cut out in a single pass

Question 104

The incident angle at which the longitudinal mode is refracted at 90° is

a) 27 degrees
b) the first critical angle
c) the second critical angle
d) not used in NDT

Answer 104

b) the first critical angle

Question 105

The fundamental frequency of a piezoelectric crystal used in ultrasonics is a function of

a) its thickness
b) the velocity of sound in the crystal material
c) both a and b
d) none of the above

Answer 105

c) both a and b

Question 106

Pulse-echo ultrasonic testing is used for

a) thickness testing
b) flaw detection
c) acoustic velocity determinations
d) all of the above

Answer 106

d) all of the above

Question 107

Ultrasonic testing of concrete would be carried out using frequencies in the range of

a) 100 to 500 Hz
b) 25 to 100 kHz
c) 0.5 to 1 MHz
d) 2 to 4 MHz

Answer 107

b) 25 to 100 kHz

Question 108

Velocity of ultrasonic waves in steel at 10°C. as compared to 40°C. are

a) slower
b) faster
c) the same
d) dependant on the alloy of steel maybe faster or slower

Answer 108

b) faster

Question 109

The parallel of mechanical resonance frequency of a piezoelectric element occurs when the element thickness is

a) one quarter wavelength
b) one half wavelength
c) one wavelength
d) none of the above

Answer 109

b) one half wavelength

Question 110

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

Answer 110

d) all of the above

Question 111

In ultrasonic testing by pulse-echo method, the sound waves off the probe are

a) omni-directional
b) a single frequency
c) a range of frequencies
d) non-existent in the dead zone

Answer 111

c) a range of frequencies

Question 112

Rayleigh, shear and longitudinal describe

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

Answer 112

b) wave modes

Question 113

Another term for the suppression control on an ultrasonic machine is

a) reject
b) damping
c) attenuation
d) gain

Answer 113

a) reject

Question 114

Surface wave testing would be used to detect

a) lamination in 10mm thick plate
b) microshrinkage in magnesium castings
c) slag inclusions in submerged arc welds
d) fatigue cracks in helicopter blades

Answer 114

d) fatigue cracks in helicopter blades

Question 115

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

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

Answer 115

b) diffraction

Question 116

A plane longitudinal wave strikes a water-steel interface from water ( V long water=1.5Km/s V long steel= 5.9km/s V shear
steel=3.2km/s ) at normal incidence. Having had a 2mm wavelength in water it will result in the shear wave wavelength being

a) 2.6mm
b) 1.5mm
c) 0.8 mm
d) none of the above, a shear wave does not occur

Answer 116

d) none of the above, a shear wave does not occur

Question 117

A contact probe which introduces an ultrasonic wave into a test piece so that the beam angle in the test piece is a some angle
other than 0 or 90 degrees to the normal is called a(n)

a) angle probe or angle beam probe
b) shear wave probe
c) dry coupling probe
d) Rayleigh probe

Answer 117

a) angle probe or angle beam probe

Question 118

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

a) power intensity
b) frequency
c) wavelength
d) acoustic impedance

Answer 118

d) acoustic impedance

Question 119

The gain required to compensate for differences in coupling efficiency between a reference or calibration block and the work
piece is called

a) transfer correction or transfer value
b) absorption coefficient
c) scatter modulus
d) attenuation constant

Answer 119

a) transfer correction or transfer value

Question 120

According to geometric-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

Answer 120

b) decreases with distance from source

Question 121

The short wave-train produced on each excitation of an ultrasonic transducer is a(n)

a) acoustic tone burst
b) half-wave
c) pulse
d) surface acoustic wave

Answer 121

c) pulse

Question 122

Which of the following is not a magnetostrictive material

a) cobalt
b) PZT
c) nickel
d) iron

Answer 122

b) PZT

Question 123

When using the large IIW Block #1, what are the fewest number of reflections from the 100mm radius in order to calibrate a 70
degree shear wave probe for a 100mm range?

a) 1
b) 2
c) 2 1/2
d) 3

Answer 123

b) 2

Question 124

In a ferroelectric ceramic such as PZT, the curie temperature is the temperature above which

a) the piezoelectric domain structure is lost
b) water is driven out of the crystal
c) polarity reverses
d) electrodes cannot be deposited

Answer 124

a) the piezoelectric domain structure is lost

Question 125

Given a 2 MHz PZT crystal coupled to steel at an angle of incidence of 3°, what is the wavelength of the shearwave in steel if
V long is 5.9mm/µs and V shear is 3.2mm/µs?

a) 0.63 mm
b) 1.6 mm
c) 6.4 mm
d) a shear wave will not be present

Answer 125

b) 1.6 mm

Question 126

The most commonly used wave mode for angle beam testing is

a) longitudinal
b) transverse
c) Rayleigh
d) Lamb

Answer 126

b) transverse

Question 127

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

Answer 127

c) less than incidence angle

Question 128

“Delay” on the ultrasonic machine is used to

a) reduce grass level
b) compensate for range errors
c) correct for proper zero point
d) adjust lag on the pulser

Answer 128

c) correct for proper zero point

Question 129

Tubing ie. tubular products, is best inspected by ultrasonics using the __________ method.

a) pulse-echo
b) transmit-receive
c) induction coil
d) time of flight diffraction

Answer 129

a) pulse-echo

Question 130

For immersion testing, surface scale and rust can be removed by

a) steel brushes and scrapping
b) sand blasting and grinding
c) both a and b
d) none of the above, cleaning is not needed for immersion testing

Answer 130

c) both a and b

Question 131

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

Answer 131

d) second critical angle

Question 132

The ratio of vibration amplitude at resonance frequency to the amplitude of static thickness change is called

a) fo
b) fr
c) the modulus of resonance
d) Q factor

Answer 132

d) Q factor

Question 133

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 counterclockwise ellipses

Answer 133

b) right angles to the direction of wave propagation

Question 134

Attenuation of ultrasonic energy is an inherent property of all materials and is

a) a constant 0.5 dB/cm
b) variable with alloy and test frequency
c) a function of acoustic impedance
d) both b and c

Answer 134

b) variable with alloy and test frequency

Question 135

The purpose of putting one or more matching layers between the front face of a probe and the coupling medium is

a) to decrease ringing time
b) to improve coupling
c) to provide a delay line effect
d) not known by probe manufacturers

Answer 135

b) to improve coupling

Question 136

For a single crystal piezoelectric material used in an ultrasonic transducer the angle to the crystal axis that it is cut determines

a) frequency
b) direction of deformation
c) Q-factor
d) both a and b

Answer 136

b) direction of deformation

Question 137

The orientation of the defect with respect to the direction of the ultrasonic beam determines

a) whether the reflected pulse returns to the receiver
b) if immersion or contact testing is used
c) if immersion or gap testing is used
d) none of the above

Answer 137

a) whether the reflected pulse returns to the receiver

Question 138

If a signal on your CRT is 28% FSH and 6 dB gain is added to the receiver amplifier the signal will be _______ FSH.

a) 34%
b) 42%
c) 56%
d) 70%

Answer 138

c) 56%

Question 139

Acoustic imaging techniques permit the visualization of objects because

a) sound can be converted to light when passing through metal
b) of the polarity of transverse waves
c) sonoluminescence occurs in couplant
d) acoustic waves obey the same equations as optical waves

Answer 139

d) acoustic waves obey the same equations as optical waves

Question 140

Using the through transmission method of ultrasonic testing

a) no couplant is needed
b) no flaw echo is seen
c) only one transducer is used
d) fillet welds are best tested

Answer 140

b) no flaw echo is seen

Question 141

Uniformity of coupling is verified by the operator monitoring

a) backwall amplitude
b) “grass” level
c) a and b
d) calibration

Answer 141

c) a and b

Question 142

Although ingots of metal are often difficult to test by ultrasonics due to large dimensions and scatter due to grain size, it is
useful to locate

a) laminations
b) bursts
c) gross piping
d) cold shots

Answer 142

c) gross piping

Question 143

A material that exhibits dimensional changes in a magnetic field is said to be

a) electrostrictive
b) ferroelectric
c) magnetostrictive
d) electromagnetic

Answer 143

c) magnetostrictive

Question 144

The method whereby the test piece is either wholly or partially under water or other such coupling fluid is called

a) gap testing
b) jet testing
c) plate testing
d) immersion testing

Answer 144

d) immersion testing

Question 145

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 and incident ray lie in the same plane
c) both a and b
d) none of the above

Answer 145

c) both a and b

Question 146

Probe index, refracted angle, timebase and sensitivity are usually calibrated using

a) calibrator electronics
b) tuning forks
c) calibration and or reference blocks
d) the test piece itself

Answer 146

c) calibration and or reference blocks

Question 147

A typical maximum thickness range for inspecting forged steel by ultrasonics is

a) 0.5 to 1m
b) 1 to 2 m
c) 1 to 10 m
d) 10 to 100 m

Answer 147

c) 1 to 10 m

Question 148

Maximum acoustic energy is coupled from one medium to another when the acoustic impedance of the first medium is
_________ the second.

a) less than
b) greater than
c) the same as
d) twice the value of

Answer 148

c) the same as

Question 149

When inspecting a thin flat plate with a 60ø shear wave probe it is possible to see both top and bottom corners of the plate
when the beam is aimed at the plate edge. This is due to

a) ghosting
b) splitting
c) beam spread
d) none of the above

Answer 149

c) beam spread

Question 150

If the sound beam strikes a flaw at right angles and the flaw has a greater area than the beam it will

a) cause resonance
b) absorb most of the beam energy
c) cause destructive interference
d) at like a backwall

Answer 150

d) at like a backwall

Question 151

Material attached to the rear of an ultrasonic crystal to increase damping is called

a) tuning material
b) matching
c) crystal backing
d) none of the above

Answer 151

c) crystal backing

Question 152

Background indications seen on an A-scan, arising from material characteristics and/or electrical noise is termed

a) grass
b) interference
c) pick-up
d) hash

Answer 152

a) grass

Question 153

Thickness readings from ultrasonic testing can be indicated by

a) reading the position of pips on a CRT screen
b) meter or digital readout
c) graphing by a pen on strip chart paper
d) all of the above

Answer 153

d) all of the above

Question 154

A PZT transducer will loose its piezoelectric property if

a) immersed in water
b) used on a forging that has not been de-magnetized
c) used on a surface whose temperature is 140 degrees C
d) heated above its curie point

Answer 154

d) heated above its curie point

Question 155

If the “focal spot” size of the beam from a focused transducer was increased by increasing the focal length

a) sensitivity would increase
b) resolution would decrease
c) all flaws would be detected
d) no indications would be rejectable

Answer 155

b) resolution would decrease

Question 156

Sound reduction over a distance can be accounted for by

a) absorption
b) scatter
c) beam spreading
d) all of the above

Answer 156

d) all of the above

Question 157

The advantage of a short duration excitation pulse applied to a normal transducer is

a) wideband frequency operation
b) high resolution
c) reduced attenuation loses
d) all of the above

Answer 157

d) all of the above

Question 158

In ultrasonic testing, the display in which pulse amplitude is represented as a displacement along one axis and time as a
displacement along the other axis is called a(n)

a) A-scan
b) B-scan
c) C-scan
d) isometric display

Answer 158

a) A-scan

Question 159

The number of nanoseconds in 2 milliseconds is

a) 0.002
b) 2000
c) 2 X 10^6
d) 2 X 10^9

Answer 159

c) 2 X 10^6

Question 160

Of the various materials used for transducer crystals, lithium sulphate hydrate is the most critical because it

a) looses its water of crystallization above 130 degrees C
b) breaks down at excitation voltages over 500 V
c) cannot be used in immersion testing
d) all of the above

Answer 160

a) looses its water of crystallization above 130 degrees C

Question 161

The piezoelectric material first used for ultrasonic transducers is

a) PZT
b) SiO2 (quartz)
c) Na Cl
d) PVDF

Answer 161

b) SiO2 (quartz)

Question 162

The main contribution to loss of sound pressure of a beam incident on a rough surface is provided by

a) scatter
b) mode conversion
c) refraction
d) diffraction

Answer 162

a) scatter

Question 163

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

Answer 163

c) phase reversal relative to the incident wave

Question 164

Rubber tires can be inspected by ultrasonic means but it requires lower frequencies in the range of 50 kHz because

a) high frequencies delaminate the rubber
b) high frequencies uncure the rubber
c) of attenuation from scatter off the fibres
d) none of the above

Answer 164

c) of attenuation from scatter off the fibres

Question 165

Given a cube of iron (long. velocity = 5800 m/s), pulse-echo multiples are seen every 100 microseconds. What is the thickness of the iron?

a) 100 mm
b) 29 mm
c) 29 cm
d) 58 cm

Answer 165

c) 29 cm

Question 166

For normal ultrasonic contact testing of forged carbon steel and aluminum the optimum frequency range of transducers is

a) 100 to 500 kHz
b) 0.5 to 1 MHz
c) 2 to 5 MHz
d) 10 to 15 MHz

Answer 166

c) 2 to 5 MHz

Question 167

Using the pulse echo method with a 0 degrees probe (single crystal) on a flat steel plate 50mm thick, the pattern on the CRT
would appear as

a) evenly spaced multiples
b) randomly spaced multiples
c) multiples with increasing spacing between them
d) none of the above

Answer 167

a) evenly spaced multiples

Question 168

The line of maximum sound intensity in the far zone of an ultrasonic beam, and its projection back to the near zone is called
the

a) half angle of divergence
b) beam spread
c) beam profile
d) beam axis

Answer 168

d) beam axis

Question 169

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

Answer 169

b) Snell’s law

Question 170

The difference between a thickness gauge and a distance gauge is

a) the range that is measured
b) velocities involved
c) type of piezoelements used
d) all of the above

Answer 170

a) the range that is measured

Question 171

You are given a cube of material 20mm thick. By pulse-echo immersion testing you determine the multiples of this material to be separated by 6.9 microseconds, the longitudinal velocity of sound in the material is

a) 1500 m/s
b) 3450 m/s
c) 5800 m/s
d) 6900 m/s

Answer 171

c) 5800 m/s

Question 172

In contact testing using angle beam probes with removable wedges, the purpose of groves in the front of the wedge is

a) to prevent couplant buildup
b) increase resolution
c) absorb internally reflected sound
d) all of the above

Answer 172

c) absorb internally reflected sound

Question 173

Which of the following is not a consideration when choosing a couplant for ultrasonic testing

a) type of material tested
b) surface finish of test piece
c) orientation of test surface
d) nominal test frequency

Answer 173

d) nominal test frequency

Question 174

High frequency transducers, over 10 MHz, have

a) little use in contact testing
b) very thin crystals
c) good sensitivity to minute defects
d) all of the above

Answer 174

d) all of the above

Question 175

When calibrating for an inspection range of 0 to 100mm with an angle beam probe, delay on the instrument must be

a) increased
b) decreased
c) left untouched
d) adjusted to correct for the time delay in the perspex wedge

Answer 175

d) adjusted to correct for the time delay in the perspex wedge

Question 176

In order to generate mechanical displacements (ultrasound waves) in a X-cut piezoelectric crystal we must

a) squeeze the crystal
b) heat the crystal
c) apply an alternating voltage
d) none of the above

Answer 176

c) apply an alternating voltage

Question 177

In contact testing best probe contact is made on ________ surfaces.

a) flat
b) convex
c) concave
d) 250 RMS surfaces

Answer 177

a) flat

Question 178

Production line testing of high pressure ribbed tubing would use which ultrasonic technique?

a) contact testing
b) immersion testing from the outside diameter
c) immersion testing from the inside diameter
d) the bubbler technique

Answer 178

c) immersion testing from the inside diameter

Question 179

Which is not a welding defect term

a) porosity
b) slag
c) lamination
d) hot cracking

Answer 179

c) lamination

Question 180

Standing waves in any medium are result of

a) interference from reflections
b) the PRF
c) wave splitting
d) mode conversion at boundaries

Answer 180

a) interference from reflections

Question 181

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

Answer 181

b) broader in the small probe dimension

Question 182

A negative value of a reflection coefficient indicates

a) no phase change has occurred
b) 90° phase change
c) 180° phase change
d) a decrease in amplitude

Answer 182

c) 180° phase change

Question 183

Sizing of defects located in the near zone is difficult because of

a) uncertainties of sound pressure along the beam axis
b) uncertainties of sound pressure at right angles to the beam axis
c) frequency variation
d) both a and b

Answer 183

d) both a and b

Question 184

Mechanical methods of ultrasound generation

a) utilise electro-mechanical hammers
b) utilise rotating wire brushes
c) require no coupling liquids
d) all of the above

Answer 184

d) all of the above

Question 185

When performing contact weld inspection the purpose of doing a normal beam inspection of the parent metal adjacent to the weld is

a) to establish material thickness
b) to locate laminations or other impeding inclusions
c) to note variations in attenuation
d) all of the above

Answer 185

d) all of the above

Question 186

Which of the following plate defects would not be a result of inservice use?

a) stress-corrosion cracking
b) laminations
c) fatigue cracking
d) pitting

Answer 186

b) laminations

Question 187

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

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

Answer 187

b) 2.5 MHz

Question 188

The recommended refracted angle for contact shear wave inspection of plate less than 10mm thick is

a) 45°
b) 60°
c) 70°
d) all of the above

Answer 188

c) 70°

Question 189

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

Answer 189

c) far field

Question 190

So as to be utilized as ultrasonic transducers, ferroelectric ceramics must

a) be heated above their curie point
b) poled
c) be put into an electric field
d) all of the above

Answer 190

d) all of the above

Question 191

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

Answer 191

c) a node

Question 192

The most common method of ultrasonic testing of welds is

a) continuous wave resonance
b) normal beam
c) angle beam
d) through-transmission

Answer 192

c) angle beam

Question 193

In weld inspection, transverse cracks are best located by

a) scanning at right angles to the weld axis
b) scanning parallel to the weld axis
c) the lamination scan
d) immersion testing

Answer 193

b) scanning parallel to the weld axis

Question 194

The display generated so that distance along a horizontal axis is proportional to time is a(n)

a) time base
b) C-scan
c) unrectified display
d) none of the above

Answer 194

a) time base

Question 195

An acoustic lens for focusing ultrasound at a specific point in front of the transducer is made as thin as possible so as to

a) make the probe as light as possible
b) obtain the shortest focal length
c) minimize absorption
d) all of the above

Answer 195

c) minimize absorption

Question 196

An echo received from a reflector of known size and characteristics could be termed a

a) reference echo
b) spurious echo
c) ghost echo
d) solid echo

Answer 196

a) reference echo

Question 197

Transmitter voltage pulse is triggered by the

a) probe resonance
b) control pulse of the sweep generator
c) sweep delay control

Answer 197

b) control pulse of the sweep generator

Question 198

Given a 4 MHz probe radiating normally into copper, V long = 4.7 km/s V shear = 2.3km/s, the wavelength of the longitudinal wave is

a) 0.85mm
b) 1.18 mm
c) 2.36mm
d) 2.99mm

Answer 198

b) 1.18 mm

Question 199

Acoustic pressure fluctuates in the near zone due to

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

Answer 199

a) diffraction interference

Question 200

Applied voltage on a piezoelectric crystal used in a transducer requires ________ to cause mechanical displacement

a) electrodes
b) vibration
c) heat
d) all of the above

Answer 200

a) electrodes

Question 201

A presentation where-by the relative amplitude of ideal reflectors of different sizes are plotted against different distances is called

a) DGS diagrams
b) AVG diagrams
c) DAC curves
d) both a and b

Answer 201

d) both a and b

Question 202

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

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

Answer 202

c) diffraction

Question 203

Scatter generally increases with

a) increasing grain size
b) decreasing wavelength
c) increasing frequency
d) all of the above

Answer 203

d) all of the above

Question 204

Maximum amplitude response of a planar defect will usually be had when

a) its main surface is perpendicular to the sound beam
b) its main surface is parallel to the sound beam
c) its main surface is oblique to the sound beam
d) none of the above, amplitude will be about equal for a given flaw regardless of orientation

Answer 204

a) its main surface is perpendicular to the sound beam

Question 205

Amplitude response of a defect is not influenced by

a) equipment settings and probe characteristics
b) attenuation
c) defect location and orientation
d) none of the above

Answer 205

d) none of the above

Question 206

When using the “pitch-catch” method of ultrasonic testing, which is not true?

a) two piezoelectric elements are commonly used
b) all the piezoelements are mounted in one housing
c) both shear and longitudinal modes can be used
d) one element is dedicated to transmission

Answer 206

b) all the piezoelements are mounted in one housing

Question 207

If you wanted to determine the depth a large surface breaking crack extending into a plate you were inspecting using an angle beam, you would need to know

a) soundpath distance
b) actual refracted angle
c) total forward/backward travel of the probe
d) all of the above

Answer 207

d) all of the above

Question 208

As temperature of a solid increases the attenuation of sound in that object tend to

a) increase
b) decrease
c) remain constant
d) vary sinusoidally

Answer 208

a) increase

Question 209

In ultrasonic testing the term sensitivity usually refers to the test system’s ability to discern

a) small distances between defects
b) the angular separation between defects
c) the smallest size defect
d) none of the above

Answer 209

c) the smallest size defect

Question 210

Ultrasonic waves with frequencies of 400MHz to 2GHz would be used in

a) acoustic microscopy
b) concrete testing
c) ultrasonic cleaning
d) nothing, it is not possible to generate ultrasound in this range

Answer 210

a) acoustic microscopy

Question 211

Given a 10 MHz probe vibrating into water, with a velocity of 1.5 mm/µs, what is the wavelength of the longitudinal wave

a) 0.15 mm
b) 1.5 mm
c) 1.5 cm
d) 0.6 cm

Answer 211

a) 0.15 mm

Question 212

The length of a defect is calculated from

a) DGS diagrams
b) lateral probe movement
c) amplitude
d) horizontal displacement of the signal on the timebase

Answer 212

b) lateral probe movement

Question 213

Alignment of the small domains in polycrystalline ferro-electric materials, such as PZT, is called

a) poling
b) polarisation
c) both a and b
d) domaining

Answer 213

c) both a and b

Question 214

In immersion testing, the hindrance of multiple interface signals that results from the pulse bouncing between the test piece and probe on normal incidence is avoided by

a) decreasing receiver gain
b) increasing the distance between probe and work surface
c) increasing damping
d) use of the interface-lock feature

Answer 214

b) increasing the distance between probe and work surface

Question 215

Reference reflectors in calibration blocks are normally cylindrical holes because

a) they are easier to machine
b) they best represent actual defects
c) they are not as directionally dependant
d) none of the above

Answer 215

c) they are not as directionally dependant

Question 216

The angle at which an ultrasonic beam spreads in the far zone is called the

a) wave angle
b) phase angle
c) angle of repose
d) angle of divergence

Answer 216

d) angle of divergence

Question 217

A system that electronically monitors an echo signal in a gate such that an alarm is triggered if the signal exceeds a predetermined amplitude is called a / an

a) B-scan
b) go / no-go system
c) early warning system
d) sweep generator

Answer 217

b) go / no-go system

Question 218

The purpose applying ultrasound to a weld puddle during electric arc welding is to

a) prevent lack of penetration
b) increase heat in the weld puddle
c) create a finer grain structure and increase tensile strength
d) eliminate the requirement for radiographic testing

Answer 218

c) create a finer grain structure and increase tensile strength

Question 219

When trying to obtain a “noise free” signal a filter is sometimes used. If this filter limits signals to just a narrow range of frequencies it is called a _________ filter.

a) low-pass
b) high-pass
c) band-pass
d) broadpass

Answer 219

c) band-pass

Question 220

Attenuation of ultrasound by absorption is a result of

a) reflection
b) refraction
c) scatter
d) heating

Answer 220

d) heating

Question 221

The ability to separate individual defects lying closely together is called

a) sensitivity
b) resolution
c) angular acuity
d) linearity

Answer 221

b) resolution

Question 222

In pulse-echo testing there is an advantage to using short pulses to excite the transducer because

a) the dead zone is decreased
b) the frequency spectrum is broadened
c) both a and b
d) none of the above

Answer 222

c) both a and b

Question 223

A probe specially designed to be used totally under water is called a(n) _________ probe.

a) immersion
b) bubbler
c) gap
d) contact

Answer 223

a) immersion

Question 224

To inspect tubular products using the ultrasonic method,

a) longitudinal wave mode is used
b) shear wave mode is used
c) surface wave mode is used
d) all wave modes can be used

Answer 224

d) all wave modes can be used

Question 225

Flaw size is often determined by

a) comparison of probe movement with change in amplitude
b) amplitude of maximum reflection
c) both a and b
d) none of the above

Answer 225

c) both a and b

Question 226

Electrode material on the piezoelectric crystal faces, typically evaporated to about 1000 angstroms thick, is made of

a) gold
b) silver
c) chrome/gold
d) all of the above can be used

Answer 226

d) all of the above can be used

Question 227

The 3 essential elements common to all systems that use ultrasonic devices are

a) transducers, cables, couplant
b) transducers, scopes, testpiece
c) power source, transducer, converter
d) none of the above

Answer 227

c) power source, transducer, converter

Question 228

The normal presentation of ultrasonic signals on an ultrasonic machine used in NDT is

a) rectified form
b) RF form
c) B-scan
d) C-scan

Answer 228

a) rectified form

Question 229

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

Answer 229

c) the acoustic impedance of a gas is essentially zero

Question 230

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

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

Answer 230

a) near field

Question 231

The purpose of the IIW block is to determine

a) probe exit point
b) refracted angle
c) range (or depth scale)
d) all of the above

Answer 231

d) all of the above

Question 232

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

Answer 232

c) one half as fast

Question 233

Resonance methods of thickness testing are no longer commonly used. This technique utilized

a) continuous wave oscillators
b) pulsed wave packets
c) surface waves
d) none of the above

Answer 233

a) continuous wave oscillators

Question 234

The incremental fine gain control of the ultrasonic instrument is calibrated in

a) 1 or 2 dB increments
b) 6 dB increments
c) 20 dB increments
d) no increments, it is completely variable

Answer 234

a) 1 or 2 dB increments

Question 235

Which is not a characteristic of ultrasound used to evaluate materials

a) attenuation
b) density
c) magnitude of echoes
d) velocity

Answer 235

b) density

Question 236

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

Answer 236

a) higher

Question 237

In weld inspection, the longitudinal wave inspection of the plate adjacent to the weld is usually done using a frequency in the range of

a) 1-2 MHz
b) 2-6 MHz
c) 6-10 MHz
d) 10-15 MHz

Answer 237

b) 2-6 MHz

Question 238

For best results detecting a defect that may be irregularly shaped and slightly off perpendicular to the beam, the wavelength used should be

a) the size of the defect
b) as small as possible
c) as large as possible to locate the defect
d) 1 MHz

Answer 238

c) as large as possible to locate the defect

Question 239

The product of density an acoustic velocity is

a) acoustic impedance
b) electric impedance
c) specific reactivity
d) the reflection coefficient

Answer 239

a) acoustic impedance

Question 240

The result of spherical or “cup shaped” lens on the front of an ultrasonic probe is a(n)

a) point focused beam
b) line focused beam
c) asymptotic beam
d) divergent beam

Answer 240

a) point focused beam

Question 241

Boron, aluminum oxide and sapphire are often used in transducers as

a) tuning transformers
b) electrodes
c) wear faces
d) none of the above

Answer 241

c) wear faces

Question 242

Given a 2.5 MHz transducer radiating ultrasound into glycerin, what is the wavelength of the shearwave in the glycerin?

a) 2.3 mm
b) 3.2 mm
c) insufficient information provided
d) none of the above

Answer 242

d) none of the above

Question 243

Magnetostrictive principles can be used

a) for transmitting ultrasound
b) for receiving ultrasound
c) both a and b
d) none of the above

Answer 243

c) both a and b

Question 244

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

Answer 244

d) about 4 times as long

Question 245

Elastic waves can be transmitted in

a) air
b) water
c) solids
d) all of the above

Answer 245

d) all of the above

Question 246

The use of flat bottom holes for a reference standard when testing forgings is a reasonable method of flaw assessment because

a) they provide good reflectivity at all angles
b) of their ease of manufacturing
c) a single block is required for all calibrations
d) they are a good representation of the flat defects found in forgings

Answer 246

d) they are a good representation of the flat defects found in forgings

Question 247

The distance between successive points of impingement of the beam axis on the entry surface after reflecting from the opposite side is called

a) stand-off
b) skip distance
c) sound path
d) none of the above

Answer 247

b) skip distance

Question 248

For flaws immediately below the surface the best option is

a) TR or twin crystal probes
b) single crystal probes
c) multi probe configurations
d) through wall testing

Answer 248

a) TR or twin crystal probes

Question 249

The imaginary line that connects all the points of the same phase in a wave propagating in a medium is referred to as the

a) phase line
b) wave front
c) interphase index
d) refractive index

Answer 249

b) wave front

Question 250

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

Answer 250

a) greater than 20 degrees

Question 251

Backing materials used in ultrasonic transducers are used for

a) changing frequency bandwidths
b) focusing the beam
c) de-focusing the beam
d) none of the above

Answer 251

a) changing frequency bandwidths

Question 252

Maximum sensitivity of a transducer is found at the

a) probe surface
b) test surface
c) end of the near zone
d) end of the dead zone

Answer 252

c) end of the near zone

Question 253

Variations in a probes’ actual frequency and its nominal frequency by as much as 5%

a) put the probe “out of spec”
b) have significant effects on test results
c) are acceptable in NDT
d) none of the above

Answer 253

c) are acceptable in NDT

Question 254

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

Answer 254

b) mode conversion

Question 255

When using the large IIW Block #1, what are the fewest number of reflections you would need to use to calibrate a longitudinal probe for 100mm range?

a) 1
b) 2
c) 4
d) 8

Answer 255

b) 2

Question 256

X-cut quartz crystal transducers are cut with active element face at right angles to the

a) X-axis
b) Y1-axis
c) Y2-axis
d) Z-axis

Answer 256

a) X-axis

Question 257

The angle of divergence is

a) constant for a given piezoelectric material
b) applicable to the far zone only
c) increases with increasing probe dimensions
d) decreases with increasing wavelength

Answer 257

b) applicable to the far zone only

Question 258

The size and shape of ultrasonic probes used are determined primarily by

a) the level II operator
b) the specific application
c) expected defect type and orientation
d) whether contact or immersion methods are used

Answer 258

b) the specific application

Question 259

Probes used in ultrasonic contact testing are checked periodically for performance when in regular use. Which characteristic would not be checked daily?

a) probe index
b) beam angle
c) beam profile
d) overall system gain

Answer 259

c) beam profile

Question 260

In hardcopy presentations of C-scans, the item recorded is

a) a absence of signal
b) the presence of a signal
c) the depth of a signal
d) a or b

Answer 260

d) a or b

Question 261

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

Answer 261

c) first critical angle

Question 262

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

Answer 262

b) amplitude of movement

Question 263

Threshold adjustment is applied to

a) RF display of signals
b) “clean up” the noise on the baseline
c) both a and b
d) none of the above

Answer 263

b) “clean up” the noise on the baseline

Question 264

Focusing of ultrasound energy is accomplished by

a) lenses
b) shaping ceramic transducers
c) test piece geometry
d) all of the above

Answer 264

d) all of the above

Question 265

In nondestructive testing the acronym EMAT stands for

a) electromagnetic acoustic transducer
b) electrically metered automatic testing
c) energy modulated acoustic technique
d) engineers make assessment tough

Answer 265

a) electromagnetic acoustic transducer

Question 266

When establishing the relative sensitivity of higher power longitudinal wave probes on the methyl polymethacrylate insert of the IIW block

a) the total number of echoes is noted
b) the amplitude of the last echo is noted
c) the gain setting is noted
d) both a) & b)

Answer 266

d) both a) & b)

Question 267

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

Answer 267

b) vector addition

Question 268

When testing thick specimens, it may be advisable to

a) decrease the pulse repetition frequency
b) add reject
c) change to a higher frequency
d) use a delay line prob

Answer 268

a) decrease the pulse repetition frequency

Question 269

Which of the following terms is not used to describe methods of coupling ultrasonic energy into a test specimen?

a) non-invasive
b) direct contact
c) immersion
d) gap

Answer 269

a) non-invasive

Question 270

The control on an ultrasonic machine which enables electrical signals to be decreased by known values, usually dB, is called a(n)

a) attenuator
b) matching box
c) reject control
d) damping control

Answer 270

a) attenuator

Question 271

Using an unrectified A-scan presentation the dominant frequency can be determined provided you know the

a) sound path to the reference reflector
b) nominal probe frequency
c) time interval on the baseline
d) none of the above

Answer 271

c) time interval on the baseline

Question 272

The common metric term Hertz (abb.Hz) is used to indicate

a) wavelength
b) velocity of sound
c) cycles per second
d) acoustic impedance

Answer 272

c) cycles per second

Question 273

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

Answer 273

b) wavelength

Question 274

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

a) dead
b) rarified
c) subduction
d) anticline

Answer 274

b) rarified

Question 275

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

Answer 275

c) rays and straight lines

Question 276

Gain and attenuator controls on an ultrasonic machine are usually calibrated in

a) arbitrary units
b) volts
c) decibels
d) none of the above

Answer 276

c) decibels

Question 277

When scanning a test plate with angle beam probes, the operator can often determine the front and backwall position on the screen from

a) “grass mounds”
b) gates
c) the distance amplitude correction curve
d) none of the above

Answer 277

a) “grass mounds”

Question 278

With a sound velocity of 1.5mm/µs in water, the wavelength of the ultrasonic disturbance in water provided by an ultrasonic cleaning machines’ 40 kHz transducer is

a) 26mm
b) 26cm
c) 3.7mm
d) 37mm

Answer 278

d) 37mm

Question 279

If the beam from an unfocused probe strikes a concave steel surface with normal incidence from water it will

a) increase beam width
b) decrease beam width
c) be totally converted to surface waves
d) none of the above

Answer 279

b) decrease beam width

Question 280

The probe movement that maintains a constant distance from an indication while varying the direction of the beam is called

a) orbiting
b) pivoting
c) traversing
d) lateral movement

Answer 280

a) orbiting

Question 281

In ultrasonic testing, the distance travelled along the beam axis is called

a) beam path length
b) stand-off
c) corrected distance
d) none of the above

Answer 281

a) beam path length

Question 282

Electromagnetic acoustic transducers (EMATs) are made from

a) silicon chips
b) ferro-magnetic crystals
c) ferro-electric crystals
d) coils of wire

Answer 282

d) coils of wire

Question 283

To a degree, the mechanical deformation of a piezoelectric material is directly proportional to the

a) acoustic impedance of the backing
b) acoustic impedance of the piezo material
c) applied voltage
d) none of the above

Answer 283

c) applied voltage

Question 284

Angle beam wedges can be used to generate surface waves only if

a) the refracted shear wave is 90°
b) the test piece is steel
c) the test piece is cylindrically shaped
d) none of the above

Answer 284

a) the refracted shear wave is 90°

Question 285

Ultrasonics has been applied in

a) fish finders and measuring water depths
b) volume, channel and colour control of televisions
c) auto-focusing mechanisms in cameras
d) all of the above

Answer 285

d) all of the above

Question 286

A probe constructed such that the ultrasonic waves converge at a point or line is a(n)

a) dual crystal probe
b) focused probe
c) de-focused probe
d) immersion probe

Answer 286

b) focused probe

Question 287

A compression wave probe is used to generate and/or receive

a) longitudinal waves
b) shear waves
c) Rayleigh waves
d) Lamb waves

Answer 287

a) longitudinal waves

Question 288

Scatter of ultrasound at grain boundaries is a result of

a) frequency
b) in-homogenous inclusions
c) angulation
d) differences in elastic properties

Answer 288

d) differences in elastic properties

Question 289

Acoustic or electrical interference in ultrasonic testing is often called

a) baseline
b) noise
c) ghost echo
d) over attenuation

Answer 289

b) noise

Question 290

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

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

Answer 290

b) an antinode

Question 291

A flat normal beam probe has a near zone of 25mm in water. If used in direct contact on steel the near zone would be

a) 3mm
b) 6mm
c) 8mm
d) 12mm

Answer 291

b) 6mm

Question 292

A positive valve of a reflection coefficient indicates

a) no phase change has occurred
b) 90 degree phase change
c) 180 degree phase change
d) an increase in amplitude

Answer 292

a) no phase change has occurred

Question 293

Production line ultrasonic inspection of tubular test pieces is done by

a) immersion methods
b) gap methods
c) contact testing methods
d) any of the above can be used depending on the specifics of the application

Answer 293

d) any of the above can be used depending on the specifics of the application

Question 294

Resonance peaks at frequencies of odd numbered multiples of the resonance frequency are called

a) harmonics
b) PRF
c) multiple frequencies
d) sub-harmonics

Answer 294

a) harmonics

Question 295

The advantage of a longer path length in the standard perspex wedge of a common contact-angle beam transducer is

a) improved near surface resolution
b) better impedance matching
c) higher sensitivity to small defects
d) all of the above

Answer 295

a) improved near surface resolution

Question 296

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

Answer 296

b) a negative R value

Question 297

When using the IIW Block #1, the probe exit point is established using the

a) 1.5mm diameter hole
b) 100mm radius
c) 50mm diameter hole
d) perspex insert

Answer 297

b) 100mm radius

Question 298

In ultrasonic testing, attenuation studies are

a) used to study some properties of materials
b) used only in destructive tests
c) only useful when using longitudinal wave mode
d) never used

Answer 298

a) used to study some properties of materials

Question 299

In immersion testing you would normally position the

a) main bang on the left edge of the CRT
b) entrance echo on the left of the CRT
c) first backwall on the right edge of the CRT
d) none of the above

Answer 299

b) entrance echo on the left of the CR

Question 300

The advantage of quartz crystals over ceramic materials for ultrasonic transducers is

a) high curie temperature
b) its harness and ability to take a high polish
c) both a and b
d) there are no advantages of quartz over ceramics

Answer 300

c) both a and b

Question 301

Ultrasonic pulse-echo techniques are used on livestock to

a) establish fat profiles
b) modify behaviour
c) increase reproductive capability
d) all of the above

Answer 301

a) establish fat profiles