LEVEL III
Review Questions
1.
In an ultrasonic test system where signal
amplitudes are displayed, an advantage of a
frequency-independent attenuator over a
continuously variable gain control is that the:
4.
a. pulse shape distortion is less.
b. signal amplitude measured using the attenuator
is independent of frequency.
c. dynamic range of the system is decreased.
d. effect of amplification threshold is avoided.
The transmitted pulse at the output of the pulser
usually has a voltage of 100 to 1000 V, whereas the
voltages of the echoes at the input of the amplifier are
on the order of:
a. 0.001-1 V
b. 1-5 V
c. 10 V
d. 50 V
G.174-176
A.86
5.
2.
An amplifier in which received echo pulses must
exceed a certain threshold voltage before they can be
indicated might be used to:
a. suppress amplifier noise, unimportant scatter
echoes, or small discontinuity echoes that are of
no consequence.
b. provide a display with nearly ideal vertical
linearity characteristics.
c. compensate for the unavoidable effects of material
attenuation losses.
d. provide distance-amplitude correction
automatically.
G.176
3.
The output voltage from a saturated amplifier is:
a. 180° out of phase from the input voltage.
b. lower than the input voltage.
c. nonlinear with respect to the input voltage.
d. below saturation.
The intended purpose of the adjustable calibrated
attenuator of an ultrasonic instrument is to:
a. control transducer damping.
b. increase the dynamic range of the instrument.
c. broaden the frequency range.
d. attenuate the voltage applied to the transducer.
A.86
6.
Which of the following might result in increased
transmission of ultrasound within a coarse-grained
material?
a. Perform the examination with a smaller diameter
transducer.
b. Perform the examination after a grain-refining
heat treatment.
c. Change from a contact examination to an
immersion examination.
d. Change from a longitudinal to a transverse wave.
B.129
G.176, 182
45
7.
The term that is used to determine the relative
transmittance and reflectance of ultrasonic energy at
an interface is called:
11.
a. depends on the transducer, pulser, and amplifier
used.
b. decreases as the frequency is increased.
c. increases as the resolution increases.
d. is not related to mechanical damping or the
transducer.
a. acoustic attenuation.
b. interface refraction.
c. acoustic impedance ratio.
d. acoustic frequency.
B.16
8.
In a forging, discontinuities associated with
nonmetallic inclusions can most accurately be
described as being:
B.46-47, 56
12.
a. oriented parallel to the major axis.
b. parallel to the minor axis.
c. aligned with forging flow lines.
d. oriented at approximately 45° to the forging
direction.
The preferred method of ultrasonically inspecting a
complex-shaped forging:
a. is an automated immersion test of the finished
forging using an instrument containing a
calibrated attenuator in conjunction with a
C-scan recorder.
b. combines thorough inspection of the billet prior
to forging with a careful inspection of the finished
part in all areas where the shape permits.
c. is a manual contact test of the finished part.
d. is an automated immersion test of the billet prior
to forging.
The ability of a test system to separate the back
surface echo and the echo from a small discontinuity
just above this back surface:
a. depends primarily upon the pulse length
generated from the instrument.
b. is not related to the surface roughness of the part
under inspection.
c. is primarily related to the thickness of the part
under inspection.
d. is usually improved by using a larger diameter
transducer.
G.340
9.
The sensitivity of an ultrasonic test system:
A.183
13.
Transducer sensitivity is most often determined by:
a. calculations based on frequency and thickness of
the piezoelectric element.
b. the amplitude of the response from an artificial
discontinuity.
c. comparing it to a similar transducer made by the
same manufacturer.
d. determining the ringing time of the transducer.
B.102-104, 106
F.504
14.
10.
When maximum sensitivity is required from a
transducer:
a. a straight beam unit should be used.
b. large-diameter crystals are required.
c. the piezoelectric element should be driven at its
fundamental resonant frequency.
d. the bandwidth of the transducer should be as
large as possible.
A.61-62
46
Side-drilled holes are frequently used as reference
reflectors for:
a. distance-amplitude calibration for shear waves.
b. area-amplitude calibration.
c. thickness calibration of plate.
d. determining near-surface solutions.
A.194-198
15.
Notches provide good reference discontinuities when
a UT examination is conducted to primarily detect
discontinuities such as:
19.
The rate generator in B-scan equipment will
invariably be directly connected to the:
a. display intensity circuit.
b. pulser circuit.
c. RF amplifier circuit.
d. horizontal sweep circuit.
a. porosity in rolled plate.
b. inadequate penetration at the root of a weld.
c. weld porosity.
d. internal inclusions.
B.3, 79-82
A.197-198
20.
16.
The difference between a compression and shear
wave is:
In A-scan equipment, the RF pulser output voltage is
normally in the range of:
a. 1-10 V.
b. 10-100 V.
c. 100-1000 V.
d. 1000-3000 V.
a. quantitative measure.
b. relative particle vibration direction.
c. qualitative measure.
d. amplitude.
B.79
B.10-12; G.7
21.
17.
The particle motion for rayleigh waves is usually
described as:
a. sinusoidal.
b. circular.
c. elliptical.
d. shear.
a. increase.
b. decrease.
c. remain unchanged.
d. not be predicted as the response is
material-dependent.
A.45; B.66; C.1-2
18.
When contact testing, an increase in tightness of a
shrink fit to a hollow shaft will cause the ratio of the
back reflection to the metal-to-metal interface
reflection to:
Based upon wave theory and ignoring attenuation
losses, the echo amplitude of a finite reflector is:
G.475
22.
a. directly proportional to the distance to the
reflector.
b. inversely proportional to the distance to the
reflector.
c. directly proportional to the square of the
diameter of the circular reflector.
d. inversely proportional to the square of the
diameter of the circular reflector.
The frequency that can best distinguish the difference
between a large planar discontinuity and four stacked
(multiple-layered) laminations in rolled plate is:
a. 0.5 MHz
b. 1 MHz
c. 2.25 MHz
d. 5 MHz
B.85
G.97
47
23.
During immersion examination, when evaluating the
response from a contoured surface of a part,
irrelevant indications due to the contour are most
likely to appear as:
27.
The time from the start of the ultrasonic pulse until
the reverberations completely decay limits the
maximum usable:
a. pulse time-discontinuity rate.
b. pulser/receiver rate.
c. pulse repetition rate.
d. modified pulse-time rate.
a. sharp, spiked signal indications.
b. irregular signal indications.
c. broad-based signal indications.
d. grass or hash.
A.71-76
A.278
28.
24.
The pulse applied to the electrodes of the ultrasonic
transducer is:
a. electrical.
b. mechanical.
c. electromechanical.
d. piezoelectrical.
Rough surfaces can cause undesirable effects, which
are noticeable when parts are tested ultrasonically,
including:
a. annular maxima rings.
b. an increase in the width of front face echo and
consequent loss of resolving power.
c. acoustical mismatch.
d. asymmetrical modes.
A.78
A.224; C.41-42
25.
In calibrating an ultrasonic test instrument using the
responses from each of the area-amplitude type
reference blocks, the determination of the:
29.
a. vertical range is obtained.
b. pulse range is obtained.
c. resolving range is obtained.
d. horizontal range is obtained.
Rough surfaces cause the echo amplitude from
discontinuities within the part to:
a. increase.
b. decrease.
c. not change.
d. change frequency.
A.195-196
26.
Test sensitivity corrections for metal distance and
discontinuity area responses are accomplished by
using:
A.202
30.
a. 0.903 MHz.
b. 0.443 MHz.
c. 0.222 MHz.
d. 0.111 MHz.
a. an area-amplitude set of blocks.
b. a distance-amplitude and an area-amplitude set of
blocks.
c. a distance-amplitude set of blocks.
d. steel balls of varying diameter.
A.195-196
The resonant frequency of a 2 cm (0.79 in.) thick
plate of naval brass (V = 4.43 × 105 cm/s) is:
G.128, 233
31.
Resonance testing equipment generally uses:
a. pulsed longitudinal waves.
b. continuous longitudinal waves.
c. pulsed shear waves.
d. continuous shear waves.
A.478, 505
48
32.
To eliminate the decrease of sensitivity close to a wall
that is parallel to the beam direction, the transducer
used should be:
37.
a. as small as possible.
b. of as low frequency as possible.
c. large and with a frequency as small as possible.
d. large and with a frequency as high as possible.
In angle beam shear wave testing, skip distance will
__________ as the thickness of the test specimen is
increased.
a. decrease
b. not change
c. increase
d. decrease by half with double thickness
A.15
33.
Which of the following transducer materials makes
the best transmitter?
G.299-303
38.
a. Quartz.
b. Lithium sulfate.
c. Barium titanate.
d. Lead titanate.
The thickness range of UT resonance thickness gages
can be increased by:
a. using large transducers.
b. operating at the fundamental frequency.
c. operating at a harmonic frequency.
d. increasing the voltage.
B.46; F.255
34.
Of the transducer materials listed below, the most
efficient receiver is:
A.185-186
39.
a. quartz.
b. lithium sulfate.
c. barium titanate.
d. lead metaniobate.
The ability of transducers to detect echoes from small
discontinuities is a definition for:
a. resolution.
b. sensitivity.
c. definition.
d. gain.
B.46; F.255
35.
The concentration of energy in the far field of a
transducer beam is:
40.
a. greatest at the outer edges of the beam.
b. greatest at the center of the beam.
c. the same at the outer edges as in the center of the
beam.
d. directly proportional to beam width.
A.99, 211
36.
A.564
The length of the near field for a 2.5 cm (1 in.)
diameter, 5 MHz transducer placed in oil
(V = 1.4 × 105 cm/s) is approximately:
a. 0.028 cm (0.01 in.).
b. 6.25 cm (2.5 in.).
c. 22.3 cm (8.8 in.).
d. 55.8 cm (22 in.).
A.210
An extensive application of shear waves in ultrasonic
testing is the inspection of:
a. welds.
b. plate.
c. pipe and tubing.
d. castings.
A.219
49
41.
From the equation for the length of the near field, it
can be determined that the near field can be
minimized by:
45.
What would be the wavelength of the energy in lead
(V = 2.1 × 105 cm/s) if it is tested with a 25 MHz
transducer?
a. 119 cm (47 in.)
b. 0.525 cm (0.21 in.)
c. 0.0119 cm (0.005 in.)
d. 0.0084 cm (0.003 in.)
a. decreasing water travel distance.
b. increasing transducer diameter.
c. decreasing the size of reference targets.
d. decreasing test frequency.
A.210
42.
In a water (VL = 1.5 × 105 cm/s) immersion test,
ultrasonic energy is transmitted into steel (VT = 3.2 ×
105 cm/s) at an incident angle of 14°. What is the
refracted shear wave within the material?
A.37
46.
What is the transducer half-angle beam spread of a
1.25 cm diameter, 2.25 MHz transducer in water
(V = 1.5 × 105 cm/s)?
a. 2.5°
b. 3.75°
c. 37.5°
d. 40.5°
a. 13°
b. 35°
c. 31°
d. 53°
A.211
A.52-53
47.
43.
The acoustic impedance for brass (V = 4.43 ×
105 cm/s, p = 8.42 gm/cm3) is:
a. 0.53 × 105 gm/cm2s
b. 1.9 × 105 gm/cm2s
c. 9.4 × 105 gm/cm2s
d. 37 × 105 gm/cm2s
A.556
44.
The principal attributes that determine the
differences in ultrasonic velocities among materials
are:
a. frequency and wavelength.
b. thickness and travel time.
c. elasticity and density.
d. chemistry and permeability.
B.10
50
Wavelength may be defined as:
a. frequency divided by velocity.
b. the distance along a wavetrain from peak to
trough.
c. the distance from one point to the next identical
point along the waveform.
d. the distance along a wavetrain from an area of
high particle motion to one of low particle
motion.
A.567; C.1
48.
Velocity measurements in a material revealed that the
velocity decreased as frequency increased. This
material is called:
50.
a. the transducers in through-transmission face each
other, while in pitch-catch the transducers are
often side by side in the same housing.
b. the transducers in through-transmission are side
by side, while in pitch-catch the transducers are
facing each other.
c. the transducers in
through-transmission are always angle beam.
d. in through-transmission the depth of the
discontinuity is easily determined.
a. dissipated.
b. discontinuous.
c. dispersive.
d. degenerative.
C.2; G.14
49.
The difference between through-transmission and
pitch-catch techniques is that:
The sound beam emanating from a continuous wave
sound source has two zones. These are called the:
a. fresnel and fraunhofer zones.
b. fresnel and near fields.
c. fraunhofer and far fields.
d. focused and unfocused zones.
A.230; C.25
C.15; F.239
Answers
1b
15b
29b
43d
2a
16b
30d
44c
3c
17c
31b
45d
4a
18c
32d
46b
5b
19b
33c
47c
6b
20c
34b
48c
7c
21a
35b
49a
8c
22d
36a
50a
9b
23c
37c
10c
24a
38c
11a
25a
39b
12a
26b
40d
13b
27c
41d
14a
28b
42c
51
LEVEL II
Review Questions
1.
The wave mode that has multiple or varying wave
velocities is:
5.
a. longitudinal waves.
b. shear waves.
c. transverse waves.
d. lamb waves.
When angle beam contact testing a test piece,
increasing the incident angle until the second critical
angle is reached may result in:
a. total reflection of a surface wave.
b. 45° refraction of the shear wave.
c. production of a surface wave.
d. a 90° angle of refraction for the wave.
B.13; C.2
B.21
2.
Which of the following would be considered
application(s) of ultrasonic techniques?
6.
a. Determination of a material’s coefficient of
expansion.
b. Study of a material’s metallurgical structure.
c. Determination of a material’s chemical
composition.
d. Evaluation of surface tension through capillary
action.
Acoustic energy propagates in different modes.
Which of the following represents a mode?
a. High-frequency ultrasonic waves.
b. A shear wave.
c. The dissipation factor.
d. The wave movement in the direction from the
point where the energy was introduced.
B.10
A.13
7.
3.
The only significant sound wave mode that travels
through a liquid is a:
The simple experiment where a stick in a glass of
water appears disjointed at the water surface
illustrates the phenomenon of:
a. shear wave.
b. longitudinal wave.
c. surface wave.
d. rayleigh wave.
a. reflection.
b. magnification.
c. refraction.
d. diffraction.
B.11
4.
The acoustic impedance of a material is used to
determine the:
F.232
8.
a. angle of refraction at an interface.
b. attenuation within the material.
c. relative amounts of sound energy coupled
through and reflected at an interface.
d. beam spread within the material.
The crystal thickness and transducer frequency are
related. The thinner the crystal:
a. the lower the frequency.
b. the higher the frequency.
c. there is no appreciable effect.
d. the lower the attenuation.
B.47
B.16
21
9.
The random distribution of crystallographic
direction in alloys with large crystalline structures
is a factor in determining:
14.
a. the body-centered cubic crystal system.
b. the angle of refraction.
c. scattering of sound.
d. material thickness.
In Figure 1, assuming a uniform beam pattern, what
relationship would you expect to exist between the
amplitudes of the reflected laminar signals at
positions A and B?
a. 12 dB difference.
b. Equal amplitudes.
c. 2 to 1.
d. 3 to 1.
B.164
A.206; B.99
10.
The length of the zone adjacent to a transducer in
which fluctuations in sound pressure occur is mostly
affected by the:
A
a. frequency of the transducer.
b. the sound beam exit point.
c. length of transducer cable.
d. diameter of the transducer.
B
Plate
B.48
11.
Laminar reflector
The differences in signals received from identical
reflectors at different material distances from a
transducer may be caused by:
Figure 1.
a. material composition.
b. beam divergence.
c. acoustic impedance.
d. the piezoelectric effect.
15.
a. minimum at
b. maximum at
c. maximum throughout twice the angle
A.211
12.
In the far field of a uniform ultrasonic beam, sound
intensity is ____________ the beam centerline.
It is possible for a discontinuity smaller than the
transducer to produce indications of fluctuating
amplitude as the transducer is moved laterally if
testing is being performed in the:

C
 sin γ = Df 
where C is acoustic velocity, D is crystal diameter,
and f is frequency at
d. not related to orientation of
a. fraunhofer zone.
b. near field.
c. snell field.
d. shadow zone.
B.56
A.210; B.48
16.
13.
In immersion testing, the near-field effects of a
transducer may be eliminated by:
a. increasing transducer frequency.
b. using a larger diameter transducer.
c. using an appropriate water path.
d. using a focused transducer.
B.68
Which of the following may result in a long, narrow
rod if the beam divergence results in a reflection
from a side of the test piece before the sound wave
reaches the back surface?
a. Multiple indications before the first back
reflection.
b. Indications from multiple surface reflections.
c. Conversion from the longitudinal mode to shear
mode at the perimeter of the beam.
d. Loss of front-surface indications.
B.143, 161
22
17.
Where does beam divergence occur?
22.
a. Near field.
b. Far field.
c. At the crystal.
d. At the interface.
Rayleigh waves are influenced most by
discontinuities located:
a. close to or on the surface.
b. 1 wavelength below the surface.
c. 3 wavelengths below the surface.
d. 6 wavelengths below the surface.
A.211; B.49
A.39
18.
As frequency increases in ultrasonic testing, the angle
of beam divergence of a given diameter crystal:
23.
a. decreases.
b. remains unchanged.
c. increases.
d. varies uniformly through each wavelength.
a. shear wave technique.
b. longitudinal wave technique.
c. surface wave technique.
d. compressional wave technique.
A.211; B.49
19.
The ultrasonic testing technique in which finger
damping is most effective in locating a discontinuity
is the:
As the radius of curvature of a curved lens is
increased, the focal length of the lens:
B.143
24.
a. increases.
b. decreases.
c. remains the same.
d. cannot be determined unless the frequency is
known.
Lamb waves can be used to detect:
a. laminar-type discontinuities near the surface of a
thin material.
b. lack of fusion in the center of a thick weldment.
c. internal voids in diffusion bonds.
d. thickness changes in heavy plate material.
A.96-97
A.100
20.
When examining materials for planar flaws oriented
parallel to the part surface, what testing method is
most often used?
25.
a. Angle beam.
b. Through-transmission.
c. Straight beam.
d. Dual crystal.
a. 1:8.
b. 1:4.
c. 1:3.
d. 1:2.
B.149
21.
The ratio of the velocity of sound in water compared
to that for aluminum or steel is approximately:
If a contact angle beam transducer produces a 45°
shear wave in steel, the angle produced by the same
transducer in an aluminum specimen would be:
(Vsteel = 0.323 cm/μs; VAL = 0.310 cm/μs)
a. less than 45°.
b. greater than 45°.
c. 45°.
d. unknown; more information is required.
A.53; B.19
A.43, 262
26.
Which of the following scanning methods could be
classified as an immersion-type test?
a. Contact angle beam testing.
b. Surface wave technique with a plastic transducer
wedge.
c. Scanning with a wheel-type transducer with the
transducer inside a liquid-filled tire.
d. Through-transmission technique with shear
waves.
A.267-269; B.67
23
27.
In an immersion test of a piece of steel or aluminum,
the water distance appears on the display as a fairly
wide space between the initial pulse and the
front-surface reflection because of:
a. reduced velocity of sound in water as compared
to the test specimen.
b. increased velocity of sound in water as compared
to the test specimen.
c. temperature of the water.
d. viscosity of the water.
31.
When using focused transducers, nonsymmetry in a
propagated sound beam may be caused by:
a. backing material variations.
b. mode conversion.
c. diffraction characteristics.
d. irregular sound beam exit point.
B.175
32.
Ultrasonic wheel units may be used for which of the
following types of examination?
B.66; F.245
28.
Using the immersion method, a distance-amplitude
curve (DAC) for a 19 mm (0.75 in.) diameter, 5 MHz
transducer shows the high point of the DAC at the
B/51 mm (2 in.) block. One day later, the high point
of the DAC for the same transducer is at the
J/102 mm (4 in.) block. Assuming that calibration has
not changed, this would indicate that the transducer:
a. Contact testing of aluminum plates.
b. Through-transmission testing of impeller shafts.
c. Longitudinal wave and/or shear wave examination.
d. Angle beam testing on beam-to-column T-joint
complete penetration welds.
A.269; B.69
33.
a. is improving in resolution.
b. is becoming defective.
c. has the beam of a contact testing transducer.
d. has a better definition.
During straight beam testing, test specimens with
nonparallel front and back surfaces can cause:
a. partial or total loss of back reflection.
b. no loss in back reflection.
c. a widened (broad) back-reflection indication.
d. a focused (narrow) back-reflection indication.
A.196-197; B.105
A.205
29.
What law can be used to calculate the angle of
refraction within a metal for both longitudinal and
shear waves?
a. Poisson’s ratio law.
b. Snell’s law.
c. Fresnel’s field law.
d. Charles’ law.
A.52-53; B.19-20
30.
At an interface between two different materials, an
impedance difference results in:
a. reflection of the entire incident energy at the
interface.
b. absorption of sound.
c. division of sound energy into transmitted and
reflected modes.
d. refraction of the entire incident energy at the
interface.
In the immersion technique, the distance between
the face of the transducer and the test surface (water
path) is usually adjusted so that the time required to
send the sound beam through the water is:
a. equal to the time required for the sound to travel
through the test piece.
b. greater than the time required for the sound to
travel through the test piece.
c. less than the time required for the sound to travel
through the test piece.
d. greater or less than the time required for the
sound to travel through the test piece depending
on water temperature and wave characteristics.
A.262
A.52
24
34.
35.
In a B-scan display, the length of a screen indication
from a discontinuity is related to:
a. a discontinuity’s thickness as measured parallel to
the ultrasonic beam.
b. the discontinuity’s length in the direction of the
transducer travel.
c. the horizontal baseline elapsed time from left to
right.
d. the vertical and horizontal directions representing
the area over which the transducer was scanned.
40.
a. manipulate the pulser/receiver unit and the
display.
b. set the proper transducer angle.
c. set the proper index function.
d. set the proper bridge distance.
A.413-414
41.
B.27
36.
In immersion testing in a small tank, a manually
operated manipulator is used to:
Which circuit triggers the pulser and sweep circuits
in an A-scan display?
In straight (normal) beam contact testing, which of
the following would NOT result in a reduction in the
back-surface reflection amplitude?
a. the usage of a high-viscosity couplant.
b. a discontinuity that is normal to the beam.
c. a near-surface discontinuity that cannot be
resolved from the main bang (initial pulse).
d. a coarse-grain material.
a. Receiver-amplifier.
b. Power supply.
c. Clock.
d. Damping.
A.205
F.242
42.
37.
On an A-scan display, the dead zone, refers to the:
a. distance contained within the near field.
b. area outside the beam spread.
c. distance covered by the front-surface pulse width
and recovery time.
d. area between the near field and the far field.
F.267
A 152 mm (6 in.) diameter rod is being inspected for
centerline cracks. The A-scan presentation for one
complete path through the rod is as shown in Figure
2. The alarm gate should:
a. be used between points A and E.
b. be used at point D only.
c. be used between points B and D.
d. not be used for this application.
B.36-37
38.
On an A-scan display, what represents the intensity of
a reflected beam?
a. Echo pulse width.
b. Horizontal screen location.
c. Signal brightness.
d. Signal amplitude.
0
1
2
3
4
5
dB
A.179
39.
Of the following scan types, which one can be used to
produce a recording of discontinuitiy areas
superimposed over a plan view of the test piece?
a. A-scan.
b. B-scan.
c. C-scan.
d. D-scan.
0
A
1
2
B
3
C
4
5
D
6
7
8
9
10
E
Figure 2.
C.19
25
43.
In an automatic scanning immersion unit, the bridge
or carriage serves to:
47.
a. provide a guide for adjusting instrument controls
to reveal discontinuities that are considered
harmful to the end use of the product.
b. give the technician a tool for determining exact
discontinuity size.
c. provide assurance that all discontinuities smaller
than a certain specified reference reflector are
capable of being detected by the test.
d. provide a standard reflector, which exactly
simulates natural discontinuities of a critical size.
a. support the manipulator and scanner tube and to
move it about transversely and longitudinally.
b. control the angular and transverse positioning of
the scanner tube.
c. control the vertical and angular positioning of the
scanner tube.
d. raise and lower the transducer.
A.413-414
44.
When adjusting the discontinuity-locating rule for a
shear wave weld inspection, the zero point on the
rule must coincide with the:
C.34
48.
a. sound beam exit point of the wedge.
b. point directly over the discontinuity.
c. wheel transducer.
d. circular scanner.
A special scanning device with the transducer
mounted in a tire-like container filled with couplant
is commonly called:
F.265
49.
a. a rotating scanner.
b. an axial scanner.
c. a wheel transducer.
d. a circular scanner.
Which best describes a typical display of a crack
whose major surface is perpendicular to the
ultrasonic beam?
a. A broad indication.
b. A sharp indication.
c. The indication will not show due to improper
orientation.
d. A broad indication with high amplitude.
B.136-137
Which of the following is a reference reflector that is
not dependent on beam angle?
a. A flat-bottom hole.
b. A V-notch.
c. A side-drilled hole which is parallel to the plate
surface and perpendicular to the sound path.
d. A disk-shaped laminar reflector.
B.69
46.
Compensation for the variation in echo height related
to variations in discontinuity depth in the test
material is known as:
a. transfer.
b. attenuation.
c. distance-amplitude correction.
d. interpretation.
B.98, 111
45.
A primary purpose of a reference standard is to:
B.107
50.
During a straight beam ultrasonic test, a
discontinuity indication is detected that is small in
amplitude compared to the loss in amplitude of back
reflection. The orientation of this discontinuity is
probably:
a. parallel to the test surface.
b. perpendicular to the sound beam.
c. parallel to the sound beam.
d. at an angle to the test surface.
A.204-205
26
51.
A discontinuity is located having an orientation such
that its long axis is parallel to the sound beam. The
indication from such a discontinuity will be:
55.
a. large in proportion to the length of the
discontinuity.
b. small in proportion to the length of the
discontinuity.
c. representative of the length of the discontinuity.
d. such that complete loss of back reflection will
result.
B.157
52.
a. loss of signal linearity.
b. loss or lack of a received discontinuity echo.
c. focusing of the sound beam.
d. loss of interference phenomena.
B.64, 157-158
56.
Gas discontinuities are reduced to flat disks or other
shapes parallel to the surface by:
a. rolling.
b. machining.
c. casting.
d. welding.
B.49
57.
In which zone does the amplitude of an indication
from a given discontinuity diminish exponentially as
the distance increases?
A set of standard reference blocks with the same
geometrical configuration and dimensions other than
the size of the calibration reflectors, for example,
flat-bottom holes, is called a set of:
a. distance-amplitude standards.
b. area-amplitude standards.
c. variable frequency blocks.
d. beam spread measuring blocks.
a. Far-field zone.
b. Near-field zone.
c. Dead zone.
d. Fresnel zone.
B.38, 104-105
B.49
54.
As transducer diameter decreases, the beam spread:
a. decreases.
b. remains the same.
c. increases.
d. becomes conical in shape.
B.120
53.
Using a pulse echo technique, if the major plane of a
flat discontinuity is oriented at some angle other than
perpendicular to the direction of sound propagation,
the result may be:
58.
A smooth, flat discontinuity whose major plane is not
perpendicular to the direction of sound propagation
may be indicated by:
a. an echo amplitude comparable in magnitude to
the back-surface reflection, as well as complete
loss of the back-surface reflection.
b. an echo whose amplitude is steady across the
discontinuity surface.
c. an increase in backwall with no response from
discontinuity.
d. the absence of an indication.
B.157
The angle at which 90° refraction of a longitudinal
sound wave is reached is called the:
a. angle of incidence.
b. first critical angle.
c. angle of maximum reflection.
d. second critical angle.
B.21
59.
The control of voltage supplied to the vertical
deflection plates of the instrument display in an
A-scan UT setup is performed by the:
a. sweep generator.
b. pulser.
c. amplifier circuit.
d. clock timer.
E.238
27
60.
Attenuation is a difficult quantity to measure
accurately, particularly in solid materials, at the test
frequencies normally used. The overall result usually
observed includes other loss mechanisms, such as:
65.
Acoustical lenses are commonly used for contour
correction. When scanning the inside of a pipe
section by the immersion method, use a:
a. focused cup lens.
b. convex lens.
c. concave lens.
d. variable pitch lens.
a. temperature.
b. scan rate.
c. fine grain structure.
d. beam spread.
A.277-278; B.53
B.15, 164
66.
61.
The most commonly used method of producing
shear waves in a flat test part when inspecting by the
immersion method is by:
a. transmitting longitudinal waves into a part in a
direction perpendicular to its front surface.
b. using two crystals vibrating at different
frequencies.
c. angulating the search tube or manipulator to the
proper angle.
d. using Y-cut quartz crystal.
a. verification of wedge angle.
b. sensitivity calibration.
c. resolution.
d. an index point.
F.266
67.
In Figure 3, transducer C is being used to check:
a. distance calibration.
b. resolution.
c. sensitivity calibration.
d. verification of wedge angle.
B.67
62.
In Figure 3, transducer A is being used to establish:
Large grains in a metallic test specimen usually result
in:
F.267
68.
a. scatter, which becomes less pronounced as grain
size approaches wavelength.
b. increased penetration.
c. have no effect if a higher frequency is used.
d. large grass or hash or noise indications.
In Figure 3, transducer D is being used to check:
a. sensitivity calibration.
b. distance calibration.
c. resolution.
d. verification of wedge angle.
B.129, 164
63.
F.266
The total energy losses occurring in all materials is
called:
A
a. attenuation.
b. scatter.
c. beam spread.
d. interface.
D
A
B.15
64.
Delay-tip (stand-off) type contact transducers are
primarily used for:
C
a. discontinuity detection.
b. sound wave characterization.
c. thickness measurement or discontinuity detection
in thin materials.
d. attenuation measurements.
B.152-153; F.258
28
Figure 3.
69.
When the incident angle is chosen to be between the
first and second critical angles, the ultrasonic wave
generated within the part will be:
72.
a. longitudinal.
b. shear.
c. surface.
d. lamb.
In a water immersion test, ultrasonic energy is
transmitted into steel at an incident angle of 14°.
What is the angle of the refracted shear wave within
the material?
VS = 3.2 × 105 cm/s
VW = 1.5 × 105 cm/s
B.21
(Trigonometry Tables Required)
70.
In Figure 4, transducer B is being used to check:
a. 45°
b. 23°
c. 31°
d. 13°
a. the verification of wedge angle.
b. resolution.
c. sensitivity calibration.
d. distance calibration.
B.21-22
F.266
73.
B
If you were requested to design a plastic shoe to
generate a rayleigh wave in aluminum, what would
be the incident angle of the ultrasonic energy?
D
VA = 3.1 × 105 cm/s
VP = 2.6 × 105 cm/s
B
(Trigonometry Tables Required)
a. 37°
b. 57°
c. 75°
d. 48°
C
B.21-22
Figure 4.
74.
71.
The angle at which 90° refraction of the shear wave
mode occurs is called the:
Compute the wavelength of ultrasonic energy in lead
at 1 MHz.
VL = 2.1 × 105 cm/s
V=λ×F
a. first critical angle.
b. second critical angle.
c. third critical angle.
d. angle of reflection.
B.21
a. 0.21 cm
b. 21 cm
c. 0.48 cm
d. 4.8 × 105 cm
B.5
29
75.
For aluminum and steel, the longitudinal velocity is
approximately _____ the shear velocity.
79.
a. equal to
b. twice
c. half of
d. four times
a. shear waves at an angle to the threads.
b. longitudinal waves from the end of the cylinder
and perpendicular to the direction of the thread
roots.
c. surface waves perpendicular to the thread roots.
d. shear waves around the circumference of the
cylinder.
B.22
76.
In inspecting a 102 mm (4 in.) diameter threaded
steel cylinder for radial cracks extending from the
root of the threads, it would be preferable to transmit:
Water travel distance for immersion inspections
should be:
G.347
a. such that the second front reflection does not
appear between the first front and back
reflections.
b. exactly 76 mm (3 in.).
c. less than 76 mm (3 in.).
d. always equal to the thickness of the material
being inspected.
80.
In an immersion inspection of raw steel material, the
water travel distance should be:
a. exactly 76 mm (3 in.).
b. equal to 76 mm (3 in.) ±13 mm (±0.5 in.).
c. greater than one-fourth the thickness of the part.
d. equal to the thickness of a material.
B.149-150
A.262
77.
The electronic circuitry that allows selection and
processing of only those signals relating to
discontinuities that occur in specific zones of a part
is called:
81.
a. an electronic gate.
b. an electronic attenuator.
c. a distance amplitude correction circuit.
d. a fixed marker.
The angle formed by an ultrasonic wave as it enters
a medium of different velocity than the one from
which it came and a line drawn perpendicular to the
interface between the two media is called the angle of:
a. incidence.
b. refraction.
c. rarefaction.
d. reflection.
B.151-152
B.18-19
78.
When conducting a contact ultrasonic test, the grass
or irregular signals that appear in the screen display
of the area being inspected could be caused by:
82.
a. fine grains in the structure.
b. dirt in the water couplant.
c. coarse grains in the structure.
d. a thick but tapered back surface.
The process of adjusting an instrument or device to a
reference standard is referred to as:
a. angulation.
b. scanning.
c. correcting for distance-amplitude variations.
d. calibration.
A.211-212
B.37
83.
A grouping of a number of crystals in one transducer,
with all contact surfaces in the same plane and
vibrating in phase with each other to act as a single
transducer is called a:
a. focusing crystal.
b. crystal mosaic.
c. scrubber.
d. single-plane manipulator.
B.51
30
84.
The angle of reflection is:
89.
a. equal to the angle of incidence.
b. dependent on the couplant used.
c. dependent on the frequency used.
d. equal to the angle of refraction.
a. refraction.
b. rarefaction.
c. angulation.
d. reflection.
E.215
85.
The angular position of the reflecting surface of a
planar discontinuity with respect to the entry surface
is referred to as:
C.3; G.23
90.
a. the angle of incidence.
b. the angle of refraction.
c. the orientation of the discontinuity.
d. angle of reflection.
A short burst of alternating electrical energy is called:
a. a continuous wave.
b. a peaked DC voltage.
c. an ultrasonic wave.
d. a pulse.
E.210; F.233
91.
In general, shear waves are more sensitive to small
discontinuities than longitudinal waves for a given
frequency and in a given material because:
a. the wavelength of shear waves is shorter than the
wavelength of longitudinal waves.
b. shear waves are not as easily dispersed in the
material.
c. the direction of particle vibration for shear waves
is more sensitive to discontinuities.
d. the wavelength of shear waves is longer than the
wavelength of longitudinal waves.
A.182
87.
Which of the following modes of vibration exhibits
the shortest wavelength at a given frequency and in a
given material?
a. A longitudinal wave.
b. A compression wave.
c. A shear wave.
d. A surface wave.
B.149
86.
The change in direction of an ultrasonic beam when
it passes from one medium to another whose velocity
differs from that of the first medium is called:
In ultrasonic testing, the time duration of the
transmitted pulse is referred to as the:
a. pulse length or pulse width.
b. pulse amplitude.
c. pulse shape.
d. pulse distortion.
G.296-304
A.183; B.81, 197
92.
88.
The phenomenon by which a wave strikes a
boundary and changes the direction of its
propagation within the same medium is referred to
as:
In general, which of the following modes of vibration
would have the greatest penetrating power in a
coarse-grained material if the frequency of the waves
is the same?
a. Longitudinal waves.
b. Shear waves.
c. Transverse waves.
d. Rayleigh waves.
a. divergence.
b. impedance.
c. angulation.
d. reflection.
D.3, 23
C.2; E.215
31
93.
A testing technique in which the crystal or
transducer is parallel to the test surface and
ultrasonic waves enter the material being tested in a
direction perpendicular to the test surface is:
98.
Mechanical and electrical stability, insolubility in
liquids, and resistance to aging are three advantages
of transducers made of:
a. lithium sulfate.
b. barium titanate.
c. quartz.
d. rochelle salts.
a. straight beam testing.
b. angle beam testing.
c. surface wave testing.
d. lamb wave.
F.254
B.91
94.
The distance from a given point on an ultrasonic
wave to the next corresponding point is referred
to as:
99.
a. frequency.
b. wavelength.
c. velocity.
d. pulse length.
The
sin θ1 sin θ2
=
V1
V2
formula is referred to as:
a. the acoustical impedance ratio formula.
b. the phase conversion formula.
c. the fresnel zone formula.
d. Snell’s law.
B.4-5
95.
The speed with which ultrasonic waves travel
through a material is known as:
A.52-53; B.19-20
100.
a. velocity.
b. pulse repetition rate.
c. pulse recovery rate.
d. ultrasonic response.
A substance that reduces the surface tension of a
liquid is referred to as:
B.15-16
101.
a. a couplant.
b. an ultrasonic dampener.
c. a wetting agent.
d. a solvent.
The amount of energy reflected from a discontinuity
is not dependent on the:
a. size of the discontinuity.
b. orientation of the discontinuity.
c. type of discontinuity.
d. filter setting.
B.62
97.
sin θ1 sin θ2
formula is used to determine:
=
V1
V2
a. angular relationships.
b. phase velocities.
c. amount of reflected sound energy.
d. acoustic impedance.
B.5
96.
The
The ultrasonic transducers most commonly used for
discontinuity testing utilize:
B.15-16
102.
a. magnetostriction principles.
b. piezoelectric principles.
c. mode conversion principles.
d. relative dialectric principles.
If an ultrasonic wave is transmitted through an
interface of two materials in which the first material
has a higher acoustic impedance value but the same
velocity value as the second material, the angle of
refraction will be:
A.60; G.117
a. greater than the angle of incidence.
b. less than the angle of incidence.
c. the same as the angle of incidence.
d. beyond the critical angle.
A.38-39; B.21-22
32
103.
Which one of the following frequencies would
probably result in the greatest ultrasonic attenuation
losses?
108.
a. 1 MHz
b. 2.25 MHz
c. 10 MHz
d. 25 MHz
a. plan view of the block, showing the area and
position of the hole bottom as seen from the
entry surface.
b. basic test pattern showing the height of an
indication from the hold bottom and its location
in depth from the entry surface.
c. cross section of the reference block, showing the
top and bottom surfaces of the block and the
location of the hole bottom in the block.
d. cross-sectional view presentation with a vertical
signal representing the hole bottom and the
horizontal position representing its depth
position.
B.47
104.
The product of the sound velocity and the density of
a material is known as the:
a. refraction value of the material.
b. acoustic impedance of the material.
c. elastic constant of the material.
d. Poisson’s ratio of the material.
B.15-16; F.234
105.
The amplifier range over which the unsaturated
signal response increases in amplitude in proportion
to the discontinuity surface area is the:
A.180-181; B.27-28
109.
A.195
What kind of waves travel at a velocity slightly less
than shear waves and their mode of propagation is
both longitudinal and transverse with respect to the
surface?
a. Rayleigh waves.
b. Transverse waves.
c. L-waves.
d. Longitudinal waves.
B.12; F.233
110.
A.43-45; B.12-13
107.
Properties of shear or transverse waves used for
ultrasonic testing include:
a. particle motion normal to propagation direction,
and a propagation velocity that is about one-half
the longitudinal wave velocity in the same
material.
b. exceptionally high sensitivity due to low
attenuation resulting from longer wavelengths
when propagating through water.
c. high coupling efficiency because shear waves are
less sensitive to surface variables when traveling
from a coupling liquid to the part.
d. high sensitivity as a result of having a greater
wave velocity than longitudinal waves in the same
material.
a. sensitivity range.
b. vertical linearity range.
c. selectivity range.
d. horizontal linearity range.
106.
During immersion testing of an ASTM Ultrasonic
Standard Reference Block, a B-scan presentation
system will show a:
Which ultrasonic test frequency would probably
provide the best penetration in a 30 cm (12 in.) thick
specimen of coarse-grained steel?
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
One of the most common applications of ultrasonic
tests employing shear waves is for the:
a. detection of discontinuities in welds,
tube and pipe.
b. determination of elastic properties of
metallic products.
c. detection of laminar discontinuities in
heavy plate.
d. measurement of thickness of thin plate.
B.65
B.47
33
111.
Significant errors in ultrasonic thickness
measurement can occur if:
116.
a. the test frequency is varying at a constant rate.
b. the velocity of propagation deviates substantially
from an assumed constant value for a given
material.
c. water is employed as a couplant between the
transducer and the part being measured.
d. the echo-to-echo mode is used.
A.496
112.
a. pulse length of the instrument.
b. pulse recovery time.
c. frequency.
d. pulse repetition frequency.
A.187; F.252
117.
Generally, the best ultrasonic testing method for
detecting discontinuities oriented along the fusion
zone in a welded plate is:
a. an angle beam contact method using surface
waves.
b. a contact test using a straight longitudinal wave.
c. an immersion test using surface waves.
d. an angle beam method using shear waves.
A.186-187
118.
An ultrasonic testing instrument that displays pulses
representing the magnitude of reflected ultrasound as
a function of time or depth of metal is said to
contain:
a. a continuous wave.
b. an A-scan presentation.
c. a B-scan presentation.
d. a C-scan presentation.
A.182; B.30
119.
At a water-steel interface, the angle of incidence in
water is 7°. The principal mode of vibration that
exists in the steel is:
a. longitudinal.
b. shear.
c. lamb.
d. surface.
a. sweep circuit.
b. receiver.
c. pulser.
d. synchronizer.
120.
In a liquid medium, the only mode of vibration that
can exist is:
a. longitudinal.
b. shear.
c. lamb.
d. surface.
In a basic pulse echo ultrasonic instrument, the
component that produces visible signals on the
screen which are used to measure distance is called a:
a. sweep circuit.
b. marker circuit.
c. receiver circuit.
d. synchronizer.
A.180, 182, 561
B.11
34
In a basic pulse echo ultrasonic instrument, the
component that produces the time baseline is called
a:
A.187, 565
B.22
115.
In a basic pulse echo ultrasonic instrument, the
component that produces the voltage that activates
the transducer is called:
a. an amplifier.
b. a receiver.
c. a pulser.
d. a synchronizer.
A.179-180; B.26-27, 80-81; C.11-12
114.
In a basic pulse echo ultrasonic instrument, the
component that coordinates the action and timing of
other components is called a:
a. display unit.
b. receiver.
c. marker circuit or range marker circuit.
d. timing section.
B.92-95
113.
In an ultrasonic instrument, the number of pulses
produced by an instrument in a given period of time
is known as the:
121.
Most basic pulse echo ultrasonic instruments use:
126.
a. automatic readout equipment.
b. an A-scan presentation.
c. a B-scan presentation.
d. a C-scan presentation.
a. parallel to the direction of propagation of the
ultrasonic beam.
b. transverse to the direction of beam propagation.
c. limited to the material surface and elliptical in
motion.
d. polarized in a plane at 45° to the direction of
beam propagation.
A.179; F.241
122.
The instrument displays a plan view of the part
outline and discontinuities when using:
A.36, 39
a. automatic readout equipment.
b. an A-scan presentation.
c. a B-scan presentation.
d. a C-scan presentation.
127.
An ultrasonic longitudinal wave travels in aluminum
with a velocity of 635 000 cm/s and has a frequency
of 1 MHz. The wavelength of this ultrasonic wave is:
a. 6.35 mm (0.25 in.).
b. 78 mm (3.1 in.).
c. 1.9 m (6.35 ft).
d. 30 000 Å.
A.181; C.19
123.
The motion of particles in a shear wave is:
The incident angles at which 90° refraction of
longitudinal and shear waves occurs are called the:
A.37
a. normal angles of incidence.
b. critical angles.
c. angles of maximum reflection.
d. mode angles.
128.
B.21; C.4
124.
125.
a. impedance ratio (r = ZWZM) of water to metal.
b. relative velocities of sound in water and metal.
c. frequency of the ultrasonic beam.
d. density ratio of water to metal.
Compression 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.
The refraction angle of longitudinal ultrasonic waves
passing from water into a metallic material at angles
other than normal to the interface is primarily a
function of the:
A.46, 52-53
129.
B.10
In contact testing, shear waves can be induced in the
test material by:
A.46
a. placing an X-cut crystal directly on the surface of
the materials and coupling through a film of oil.
b. using two transducers on opposite sides of the
test specimen.
c. placing a spherical acoustic lens on the face of the
transducer.
d. using a transducer mounted on a plastic wedge so
that sound enters the part at an angle.
The mode of vibration that is quickly damped out
when testing by the immersion method is:
a. longitudinal waves.
b. shear waves.
c. transverse waves.
d. surface waves.
A.217
35
130.
As frequency increases in ultrasonic testing, the angle
of beam divergence of a given diameter crystal:
135.
In steel, the velocity of sound is greatest in:
a. longitudinal waves.
b. shear waves.
c. surface waves.
d. lamb waves.
a. decreases.
b. remains unchanged.
c. increases.
d. varies uniformly through each wavelength.
A.43
A.96, 211
136.
131.
Which of the following is not an advantage of contact
ultrasonic transducers (probes) adapted with plastic
shoes?
a. Most of the crystal wear is eliminated.
b. Adaptation to curved surfaces is permitted.
c. Sensitivity is increased.
d. Ultrasound is allowed to enter a part’s surface at
oblique angles.
a. used to calculate the angle of reflection.
b. the product of the density of the material and the
velocity of sound in the material.
c. found by Snell’s law.
d. used to determine resonance values.
A.96, 98, 556
137.
A.74-75
132.
The velocity of sound is the lowest in:
B.154-155
A.43; F.235
138.
A longitudinal ultrasonic wave is transmitted from
water into steel at an angle of 5° from the normal.
In such a case, the refracted angle of the transverse
wave is:
a. less than the refracted angle of the longitudinal
wave.
b. equal to the refracted angle of the longitudinal
wave.
c. greater than the refracted angle of the
longitudinal wave.
d. not present at all.
A.46, 52-53
134.
Thin sheet may be inspected with the ultrasonic wave
directed normal to the surface by observing the:
a. amplitude of the front-surface reflection.
b. multiple reflection pattern.
c. attenuation rate.
d. ratio of shear and longitudinal velocities.
a. air.
b. water.
c. aluminum.
d. plastic.
133.
The acoustic impedance is:
The velocity of longitudinal waves is the highest in:
A diagram in which the entire circuit stage or
sections are shown by geometric figures and the path
of the signal or energy by lines and/or arrows is
called a:
a. schematic diagram.
b. blueprint.
c. block diagram.
d. circuit layout.
A.85, 157
139.
A void caused by gas entrapped in a casting is called:
a. a burst.
b. a cold shut.
c. flaking.
d. a blowhole.
B.128
a. water.
b. air.
c. aluminum.
d. plastic.
A.43; F.236
36
140.
A discontinuity that occurs during the casting of
molten metal which may be caused by the splashing,
surging, interrupted pouring, or the meeting of two
streams of metal coming from different directions is
called:
144.
a. low enough so that transmitted waves will not
interfere with reflected signals.
b. immaterial as the pulse repetition rate does not
affect the ability to detect indications regardless of
size.
c. slow enough to allow the instrument display to
refresh with each pulse.
d. fast enough for the operator to be able to rely on
the discontinuity alarm instead of constantly
watching the screen.
a. a burst.
b. a cold shut.
c. flaking.
d. a blowhole.
B.128
141.
The ratio between the wave speed in one material
and the wave speed in a second material is called:
a. the acoustic impedance of the interface.
b. Young’s modulus.
c. Poisson’s ratio.
d. refractive index.
A.187
145.
The expansion and contraction of a magnetic
material under the influence of a changing magnetic
field is referred to as:
A.262, 556
146.
a. piezoelectricity.
b. refraction.
c. magnetostriction.
d. rarefaction.
The ratio of stress to strain in a material within the
elastic limit is called:
a. Young’s modulus.
b. the impedance ratio.
c. Poisson’s ratio.
d. refractive index.
A quartz crystal cut so that its major faces are parallel
to the Z and Y axes and perpendicular to the X axis is
called:
a. a Y-cut crystal.
b. an X-cut crystal.
c. a Z-cut crystal.
d. a ZY-cut crystal.
A.116
143.
The factor that determines the amount of reflection
at the interface of two dissimilar materials is:
a. the index of rarefaction.
b. the frequency of the ultrasonic wave.
c. Young’s modulus.
d. the acoustic impedance.
A.564
142.
When setting up for an ultrasonic inspection, the
pulse repetition rate of the instrument must be:
A.558
147.
The equation describing wavelength in terms of
velocity and frequency is:
a. wavelength = velocity × frequency.
b. wavelength = z (frequency × velocity).
c. wavelength = velocity ÷ frequency.
d. wavelength = frequency + velocity.
A.319, 482
A.37; D.2
148.
When an ultrasonic beam reaches the interface of
two dissimilar materials, it can be:
a. 100% reflected.
b. 100% absorbed.
c. partially reflected and refracted, but not absorbed.
d. partially reflected, refracted, and transmitted.
A.54, 221, 237 Fig.7
37
149.
When inspecting aluminum by the immersion
method using water for a couplant, the following
information is known:
velocity of sound in water = 1.49 × 105 cm/s,
velocity of longitudinal waves in aluminum =
6.32 × 105 cm/s, and angle of incidence = 5°.
The angle of refraction for longitudinal waves is
approximately:
153.
Beam divergence is a function of the dimensions of
the crystal and the wavelength of the beam
transmitted through a medium, and it:
a. increases if the frequency or crystal diameter
decreases.
b. decreases if the frequency or crystal diameter
decreases.
c. increases if the frequency increases and crystal
diameter decreases.
d. decreases if the frequency increases and crystal
diameter decreases.
a. 22°
b. 18°
c. 26°
d. 16°
B.47, 49
A.46, 52-53; D.6
154.
150.
Of the piezoelectric materials listed below, the most
efficient sound transmitter is:
The wavelength of an ultrasonic wave is:
a. directly proportional to velocity and frequency.
b. directly proportional to velocity and inversely
proportional to frequency.
c. inversely proportional to velocity and directly
proportional to frequency.
d. equal to the product of velocity and frequency.
a. lithium sulfate.
b. quartz.
c. barium titanate.
d. silver oxide.
B.46; F.255
151.
Of the piezoelectric materials listed below, the most
efficient sound receiver is:
D.2
155.
a. lithium sulfate.
b. quartz.
c. barium titanate.
d. silver oxide.
The fundamental frequency of a piezoelectric crystal
is primarily a function of the:
a. length of the applied voltage pulse.
b. amplifying characteristics of the pulse amplifier in
the instrument.
c. thickness of the crystal.
d. material testing.
F.255
B.47; E.223
152.
The most commonly used method of producing
shear waves in a test part when inspecting by the
immersion method is by:
156.
a. transmitting longitudinal waves into a part in a
direction perpendicular to its front surface.
b. using two crystals vibrating at different
frequencies.
c. using a Y-cut quartz crystal.
d. angulating the search tube to the proper angle.
F.258
Acoustic velocities of materials are primarily due to
the material’s:
a. density and elasticity.
b. material thickness.
c. temperature.
d. acoustic impedance.
D.2; G.13
157.
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.
B.129; F.190
38
158.
Lamb waves may be used to inspect:
163.
a. forgings.
b. bar stock.
c. ingots.
d. thin sheet.
a. all crystals be mounted equidistant from each
other.
b. the intensity of the beam pattern not vary greatly
over the entire length of the transducer.
c. the fundamental frequency of the crystals not
vary more than 0.01%.
d. the overall length not exceed 76 mm (3 in.).
B.14
159.
The primary requirement of a paintbrush transducer
is that:
The formula used to determine the angle of beam
divergence of a quartz crystal is:
F.258
a. sin θ = diameter r 1/2 × wavelength.
b. sin θ diameter = frequency × wavelength.
c. sin θ = frequency × wavelength.
d. sin θ/2 = 1.22 × wavelength/diameter.
164.
Heat conduction, viscous friction, elastic hysteresis,
and scattering are four different mechanisms that
lead to:
B.49
160.
a. attenuation.
b. refraction.
c. beam spreading.
d. saturation.
The resolving power of a transducer is directly
proportional to its:
a. diameter.
b. bandwidth.
c. pulse repetition.
d. Poisson’s ratio.
F.238
165.
F.255
161.
Acoustic lens elements with which of the following
permit focusing the sound energy to enter cylindrical
surfaces normally or along a line focus?
a. Cylindrical curvatures.
b. Spherical lens curvatures.
c. Convex shapes.
d. Concave shapes.
Because the velocity of sound in aluminum is
approximately 245 000 in./s, for sound to travel
through 25 mm (1 in.) of aluminum, it takes:
a. 1/8 s
b. 4 μs
c. 4 ms
d. 1/4 ×104 s
F.233
166.
When testing a part with a rough surface, it is
generally advisable to use a:
F.259
162.
In the basic pulse echo instrument, the synchronizer,
clock or timer circuit determines the:
a. pulse length.
b. gain.
c. pulse repetition rate.
d. sweep length.
F.242
a. lower frequency transducer and a more viscous
couplant than is used on parts with a smooth
surface.
b. higher frequency transducer and a more viscous
couplant than is used on parts with a smooth
surface.
c. higher frequency transducer and a less viscous
couplant than is used on parts with a smooth
surface.
d. lower frequency transducer and a less viscous
couplant than is used on parts with a smooth
surface.
B.62
39
167.
Reflection indications from a weld area being
inspected by the angle beam technique may
represent:
172.
a. porosity.
b. backwall.
c. initial pulse.
d. hot tears.
To evaluate and accurately locate discontinuities after
scanning a part with a paintbrush transducer, it is
generally necessary to use a:
a. transducer with a smaller crystal.
b. scrubber.
c. grid map.
d. crystal collimator.
B.134-142
168.
During a test using A-scan equipment, strong
indications that move at varying rates across the
screen in the horizontal direction appear. It is
impossible to repeat a particular screen pattern by
scanning the same area. A possible cause of these
indications is:
B.51
173.
a. porosity in the test part.
b. an irregularly shaped crack.
c. a blowhole.
d. electrical interference.
a. the same as the area of the 2 mm (0.08 in.)
flat-bottom hole.
b. greater than the area of the 2 mm (0.08 in.)
flat-bottom hole.
c. slightly less than the area of the 2 mm (0.08 in.)
flat-bottom hole.
d. about one-half the area of the 2 mm (0.08 in.)
flat-bottom hole.
F.246
169.
In an A-scan presentation, position along the
horizontal baseline indicates:
a. a square wave pattern.
b. a sweep line.
c. a marker pattern.
d. elapsed time.
F.262
174.
B.26
170.
The greatest amount of attenuation losses take place
at:
F.234
B.15
Waves that travel around gradual curves with little or
no reflection from the curve are called:
a. transverse waves.
b. surface waves.
c. shear waves.
d. longitudinal waves.
175.
Lower frequency sound waves are not generally used
for pulse echo testing of thinner materials because of:
a. the rapid attenuation of low frequency sound.
b. incompatible wavelengths.
c. poor near-surface resolution.
d. fraunhofer field effects.
F.234
B.12-13
40
As the impedance ratio of two dissimilar materials
increases, the percentage of sound coupled through
an interface of such materials:
a. decreases.
b. increases.
c. is not changed.
d. may increase or decrease.
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
171.
An ultrasonic instrument has been calibrated to
obtain an 80% FSH indication from a 2 mm (0.08 in.)
diameter flat-bottom hole located 76 mm (3 in.) from
the front surface of an aluminum reference block.
When testing an aluminum forging, an 80% FSH
indication is obtained from a discontinuity located
76 mm (3 in.) from the entry surface. The reflective
area of this discontinuity is probably:
176.
In immersion testing, the accessory equipment to
which the search cable and the transducer are
attached is called a:
181.
Which of the following is more likely to limit the
maximum scanning speed in immersion testing?
a. The frequency of the transducer.
b. Viscous drag problems.
c. The pulse repetition rate of the test instrument.
d. The persistency of the ultrasonic instrument
display.
a. crystal collimator.
b. scrubber.
c. jet-stream unit.
d. search tube or scanning tube.
B.123
177.
In general, discontinuities in wrought products tend
to be oriented:
A.403
182.
a. randomly.
b. in the direction of grain flow.
c. at right angles to the entry surface.
d. at right angles to the grain flow.
The property of certain materials to transform
electrical energy to mechanical energy and vice versa
is called:
a. mode conversion.
b. piezoelectric effect.
c. refraction.
d. impedance matching.
B.126
A.60; B.45
178.
In immersion testing of round bars, the back surface
contour may result in:
183.
a. loss of back reflection.
b. additional indications following the direct back
surface reflection.
c. inability to distinguish the actual distance to the
back-surface reflection.
d. false indications of discontinuities near the back
surface.
A.275, 277-278
179.
a. 25 mm (1 in.).
b. 102 mm (4 in.).
c. 1 wavelength.
d. 4 wavelengths.
A.39
184.
In contact testing, discontinuities near the entry
surface cannot always be detected because of:
a. the far-field effect.
b. attenuation.
c. the dead zone.
d. refraction.
In cases where the diameter of tubing being inspected
is smaller than the diameter of the transducer, what
can be used to confine the sound beam to the proper
range of angles?
a. A scrubber.
b. A collimator.
c. An angle plane angulator.
d. A jet-stream unit.
A.290-291
To prevent the appearance of the second front surface
indication before the first back reflection when
inspecting aluminum by the immersion method
(water is used as a couplant), it is necessary to have a
minimum of at least 25 mm (1 in.) of water for every
_____ of aluminum.
a. 51 mm (2 in.)
b. 102 mm (4 in.)
c. 152 mm (6 in.)
d. 203 mm (8 in.)
A.204; B.58
180.
Surface waves energy levels are concentrated at what
depth below the surface?
F.258
185.
Increasing the length of the pulse used to activate the
transducer will:
a. increase the strength of the ultrasound but
decrease the resolving power of the instrument.
b. increase the resolving power of the instrument.
c. have no effect on the test.
d. decrease the penetration of the sound wave.
B.36
41
186.
The lack of parallelism between the entry surface and
the back surface:
191.
a. may result in a screen pattern that does not
contain back reflection indications.
b. makes it difficult to locate discontinuities that lie
parallel to the entry surface.
c. usually indicates that a porous condition exists in
the metal.
d. decreases the penetrating power of the test.
In a plate, skip distance can be calculated from which
of the following formulas where (t = plate thickness,
θ = angle of sound beam refraction, and V = sound
velocity):
a. S = (2 × t)/tan θ.
b. S = 2 × t × sin θ.
c. S = 2 × t × tan θ.
d. S = 2 ×V × sin θ.
F.266
B.148-151
192.
187.
A discontinuity with a concave surface will:
a. diffuse the sound energy throughout the part.
b. cause the reflected beam to focus at a point
determined by the curvature of the discontinuity.
c. cause mode reinforcement of the ultrasonic wave.
d. propagate due to sound energy.
a. distinguish between different types of
discontinuities.
b. predict the useful service life of the test specimen.
c. distinguish between discontinuity indications and
spurious or false indications.
d. accept an indication that appeared to be rejectable
from the first test direction.
B.140
188.
The technique of examining an ultrasonic reflector
from different directions might be used to enable the
technician to:
Rayleigh waves:
F.247
a. are generated at the first critical angle.
b. are generated at the second critical angle.
c. are generated at either critical angle.
d. travel only in a liquid.
193.
Attenuation is the loss of the ultrasonic wave energy
during the course of propagation in the material due
to:
F.236, 257
189.
a. cracks that are perpendicular to the sound wave.
b. inclusions that are randomly oriented.
c. laminations that are parallel to the front surface.
d. a series of small discontinuities.
F.270
190.
Reducing the extent of the dead zone of a transducer
by using a delay tip results in:
a. improved distance-amplitude correction in the
near field.
b. reduced frequency of the primary ultrasonic
beam.
c. reduced ability to detect discontinuities in the
near field.
d. improved accuracy in thickness measurement of
thin plate and sheet.
F.258
42
a. reflection and refraction.
b. dispersion and diffraction.
c. absorption and scattering.
d. composition and shape.
Angle beam testing of plate will often miss:
B.15
194.
In immersion shear wave testing, waves are normally
generated by angulating the transducer beyond the
first critical angle. What is the direction of the
material’s particle motion?
a. The same as the wave propagation.
b. Normal to the material surface.
c. Parallel to the direction of wave propagation.
d. Perpendicular to the direction of wave
propagation.
F.233
195.
Which of the following modes of vibration are
quickly dampened out when testing by the
immersion method?
197
a. Longitudinal waves.
b. Shear waves.
c. Transverse waves.
d. Surface waves.
A quartz crystal cut so that its major faces are parallel
to the Z and Y axes and perpendicular to the X axis is
called:
a. a Y-cut crystal.
b. an X-cut crystal.
c. a Z-cut crystal.
d. a ZY-cut crystal.
B.157
196.
A.558
Which ultrasonic test frequency would probably
provide the best penetration in a 30 cm (12 in.) thick
specimen of coarse-grained steel?
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
B.47
Answers
1d
15b
29b
43a
57b
71b
85c
99d
113b
127a
141d
155c
169d
183c
197b
2b
16c
30c
44a
58b
72c
86d
100a
114a
128b
142c
156a
170d
184b
3b
17b
31a
45c
59c
73b
87a
101d
115a
129d
143a
157b
171b
185a
4c
18a
32c
46b
60d
74a
88d
102c
116d
130a
144a
158d
172a
186a
5c
19a
33a
47a
61c
75b
89a
103d
117d
131c
145d
159d
173b
187b
6b
20c
34b
48c
62d
76a
90d
104b
118c
132a
146b
160b
174a
188b
7c
21a
35b
49c
63a
77a
91a
105b
119a
133a
147c
161a
175c
189c
8b
22a
36c
50d
64c
78c
92a
106a
120b
134c
148d
162c
176d
190d
9c
23c
37c
51b
65b
79b
93a
107a
121b
135a
149a
163b
177b
191c
10d
24a
38d
52a
66d
80c
94b
108c
122d
136b
150c
164a
178a
192a
11b
25b
39c
53a
67c
81b
95a
109a
123b
137b
151a
165b
179c
193c
12b
26c
40b
54a
68d
82d
96c
110a
124a
138c
152d
166a
180b
194d
13c
27a
41a
55b
69b
83b
97b
111b
125d
139d
153a
167a
181c
195d
14c
28b
42c
56c
70b
84a
98c
112d
126b
140b
154b
168d
182b
196a
43
Level I
Review Questions
1.
The indication on the instrument display that
represents the far boundary of the material being
tested is called:
5.
a. lamb wave.
b. shear wave.
c. longitudinal wave.
d. transverse wave.
a. grass or hash.
b. the initial pause.
c. the main bang.
d. the back-surface reflection.
A.557; B.10
A.205; B.26
2.
Another name for a compressional wave is:
6.
In immersion testing, the position of the transducer
is often varied by a manipulator to transmit sound
into the test part at various angles to the front
surface. Such a procedure is referred to as:
Another name for rayleigh waves is:
a. shear waves.
b. longitudinal waves.
c. transverse waves.
d. surface waves.
A.43; B.10
a. angulation.
b. dispersion.
c. reflection testing.
d. refraction.
7.
A.267, 268, 413, 414; B.196
3.
The technical name for the cable that connects the
ultrasonic instrument to the transducer is:
a. BX cable.
b. conduit.
c. coaxial cable.
d. ultrasonic conductor cable-grade 20.
a. a wetting agent.
b. a couplant.
c. an acoustic transmitter.
d. a lubricant.
A.15; B.61
8.
A.79; B.45
4.
A material used between the face of a transducer
and the test surface to permit or improve the
transmission of ultrasonic vibrations from the
transducer to the material being tested is called:
The process of standardizing an instrument or device
by using a reference standard is called:
a. angulation.
b. calibration.
c. attenuation.
d. correlation.
The piezoelectric material in a transducer that
vibrates to produce ultrasonic waves is called a:
a. backing material.
b. plastic wedge.
c. crystal.
d. couplant.
A.60; B.46
A.557; B.37
1
9.
Ultrasonic testing of material where the probe is in
direct contact with the material being tested may be:
12.
a. water jet.
b. immersion testing.
c. air coupled.
d. straight beam testing.
The transducer that contains the thinnest
piezoelectric crystal is a:
a. 1 MHz transducer.
b. 5 MHz transducer.
c. 15 MHz transducer.
d. 25 MHz transducer.
A.202; B.63
10.
An advantage of using lithium sulfate in transducers
is that it:
a. is one of the most efficient generators of
ultrasonic energy.
b. is one of the most efficient receivers of
ultrasonic energy.
c. is insoluble.
d. can withstand temperatures as high as
700 °C (1260 °F).
B.47
13. Penetration of ultrasonic waves in a material is
normally the function of test frequency used. The
greatest depth of penetration is provided by a
frequency of:
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
B.46
11.
The transducer shown in Figure 1 is used for:
D.47
14.
a. surface wave testing.
b. angle beam testing.
c. immersion testing.
d. straight beam testing.
The amount of beam divergence from a crystal is
primarily dependent on the:
a. type of test.
b. tightness of crystal backing in the transducer.
c. frequency and crystal size.
d. pulse length.
B.55
A.211; B.49
15.
When an ultrasonic beam passes through the
interface between two dissimilar materials at an
angle, a new angle of sound travel takes place in the
second material due to:
a. attenuation.
b. rarefaction.
c. compression.
d. refraction.
A.38, 564; B.18-19
Figure 1.
2
(No sweep delay is being used)
1
2
3
4
5
152 mm (6 in.)
203 mm (8 in.)
0
0
1
2
A
3
4
B
C
5
6
D
7
8
9
10
E
Figure 2.
16.
Figure 2 illustrates a contact test on a 203 mm
(8 in.) aluminum block. A discontinuity is located
152 mm (6 in.) from the front surface. The display
representation for this is shown to the right. What
does indication A represent?
a. The initial pulse or front-surface indication.
b. The first discontinuity indication.
c. The first back-surface reflection.
d. Baseline.
19.
a. first discontinuity indication.
b. second indication of the discontinuity.
c. first back-surface reflection.
d. second back-surface reflection.
A.204; B.26
20.
In Figure 2, indication B represents:
a. the initial pulse or front-surface indication.
b. the first discontinuity indication.
c. the first back-surface reflection.
d. baseline.
A.203, 204; B.26
18.
In Figure 2, indication C represents the:
In Figure 2, indication E represents the:
a. first discontinuity indication.
b. second indication of the discontinuity.
c. first back-surface reflection.
d. second back-surface reflection.
A.203, 204; B.26
17.
In Figure 2, indication D represents the:
A.205; B.26
21.
The velocity of longitudinal waves is approximately
______ the velocity of shear waves in the same
material.
a. two times
b. four times
c. 1/2
d. 9/10
a. second back-surface reflection.
b. first discontinuity indication.
c. second indication of the discontinuity.
d. first back-surface reflection.
B.12
A.205; B.26
3
22.
Figure 3 illustrates an immersion test of a 76 mm
(3 in.) block of aluminum with a discontinuity
located 51 mm (2 in.) below the surface. The display
pattern is shown also. What does indication A
represent? Assume no sweep delay is used.
25 mm (1 in.)
76 mm
(3 in.)
a. The first front-surface indication.
b. The initial pulse.
c. The first discontinuity indication.
d. The first back-surface reflection.
51 mm
(2 in.)
Aluminum
A
Water
B
C
D
B.17; F.245
23.
Figure 3.
In Figure 3, indication B represents the:
a. first front-surface indication.
b. initial pulse.
c. first back-surface reflection.
d. first discontinuity reflection.
27.
Under most circumstances, which of the following
frequencies would result in the best resolving power?
B.17; F.245
24.
a. 1 MHz
b. 5 MHz
c. 10 MHz
d. 25 MHz
In Figure 3, indication C represents the:
a. first front-surface indication.
b. first discontinuity indication.
c. first back-surface reflection.
d. second front-surface indication.
B.47
28.
B.17; F.245
25.
Which of the following materials of the same alloy is
most likely to produce the greatest amount of sound
attenuation over a given distance?
In Figure 3, indication D represents the:
a. A hand forging.
b. A coarse-grained casting.
c. An extrusion.
d. The attenuation is equal in all materials.
a. first discontinuity indication.
b. first back-surface reflection.
c. second front-surface indication.
d. second discontinuity indication.
B.164; E.221; F.238
B.17; F.245
29.
26.
In Figure 3, the distance between indications A and B
represents the:
a. distance from the front surface of the aluminum
block to the discontinuity.
b. distance from the front surface of the aluminum
block to the back surface of the aluminum block.
c. water distance from the transducer to the
aluminum block.
d. 76 mm.
B.17; F.245
In contact testing, the entry surface indication is
sometimes referred to as the:
a. initial pulse.
b. back reflection.
c. skip distance.
d. scan path.
B.80
30.
An ultrasonic instrument display pattern containing
a large number of low-level indications (often
referred to as grass or hash) could be caused by:
a. a crack.
b. a large inclusion.
c. coarse-grained material.
d. a gas pocket.
A.211; B.47, 195; E.221
4
31.
A test method employing two separate transducers
on opposite surfaces of the material being tested is
called:
36.
The number “25 million cycles per second” can also
be stated as:
a. 25 kHz.
b. 2500 kHz.
c. 25 MHz.
d. 25 μHz.
a. contact testing.
b. surface wave testing.
c. through-transmission testing.
d. lamb wave testing.
B.3
B.64-65
37.
32.
The number of complete waves that pass a given
point in a given period of time (usually 1 s) is
referred to as the:
a. scanning.
b. attenuating.
c. angulating.
d. resonating.
a. amplitude.
b. pulse length.
c. frequency.
d. wavelength.
A.564; E.250
B.4-5, 195
33.
38.
The boundary between two different materials that
are in contact with each other is called:
A term used in ultrasonics to express the rate at which
sound waves pass through various substances is:
a. frequency.
b. velocity.
c. wavelength.
d. pulse length.
a. a rarefactor.
b. a refractor.
c. an interface.
d. a marker.
A.36-37
A. 561; B.75; E.216
34.
Moving a transducer over a test surface either
manually or automatically is referred to as:
39.
When the motion of the particles of a medium is
parallel to the direction of propagation, the wave
being transmitted is called a:
When an indication has reached the maximum signal
height which can be displayed or viewed on the
display of an ultrasonic instrument, the indication is
said to have reached its:
a. distance amplitude height.
b. absorption level.
c. vertical limit.
d. limit of resolution.
a. longitudinal wave.
b. shear wave.
c. surface wave.
d. lamb wave.
A.566
B.10-11; E.210
40.
35.
When the motion of the particles of a medium is
transverse to the direction of propagation, the wave
being transmitted is called a:
An ultrasonic testing technique in which the
transducer element is not parallel to the test surface
is called:
a. angle beam testing.
b. immersion testing.
c. contact testing.
d. through-transmission testing.
a. longitudinal wave.
b. shear wave.
c. surface wave.
d. lamb wave.
B.52
B.10-11; E.210
5
41.
In Figure 4, angle 1 (θ1) is called the angle of:
45.
a. incidence.
b. reflection.
c. refraction.
d. diffraction.
In an A-scan presentation, the horizontal baseline
represents the:
a. amount of reflected ultrasonic sound energy.
b. distance traveled by the transducer.
c. elapsed time or distance.
d. signal amplitude.
B.18-20
A.179; B.26
42.
In Figure 4, angle 2 (θ2) is called the angle of:
46.
a. incidence.
b. reflection.
c. refraction.
d. diffraction.
a. amount of ultrasonic sound energy returning to
the transducer.
b. distance traveled by the transducer.
c. thickness of material being tested.
d. elapsed time since the ultrasonic pulse was
generated.
A.56
43.
In Figure 4, angle 3 (θ3) is called the angle of:
a. incidence.
b. reflection.
c. refraction.
d. rarefaction.
A.179; B.26
47.
B.18-20
1
Which of the following test frequencies would
generally provide the best penetration in a 305 mm
(12 in.) thick specimen of coarse-grained steel?
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
2
B.47
Water
48.
3
Metal
Figure 4.
44.
In an A-scan presentation, the amplitude of vertical
indications on the display represents the:
Most commercial ultrasonic testing is accomplished
using frequencies between:
In a basic ultrasonic test pattern (A-scan) for contact
testing (assuming no sweep delay is used), the initial
pulse is:
a. the high indication on the extreme left side of the
display that represents the entry surface of the
inspected part.
b. the first pulse that occurs near the right side of
the display and represents the opposite boundary
of the inspected part.
c. an indication that appears and disappears during
screening.
d. always the second pulse from the left on the
viewing display.
B.26; F.242
a. 1 and 25 kHz.
b. 1 and 1000 kHz.
c. 0.2 and 25 MHz.
d. 15 and 100 MHz.
B.47
6
49.
An ultrasonic test using a straight beam contact
transducer is being conducted through the thickness
of a flat part such as a plate. This test should detect:
52.
a. laminar-type discontinuities with major
dimensions parallel to the rolled surface.
b. transverse-type discontinuities with major
dimensions at right angles to the rolled surface.
c. radial discontinuities with major dimensions
along length but radially oriented to the rolled
surface.
d. rounded discontinuities such as porosity.
a. avoid a large number of back reflections that
could interfere with a normal test pattern.
b. obtain a maximum response if the discontinuity is
not originally oriented perpendicular to the
ultrasonic beam.
c. obtain the maximum number of entry surface
reflections.
d. obtain a discontinuity indication of the same
height as the indication from the flat-bottom hole
in a reference block.
B.120-121; G.380
50.
In ultrasonic testing, a liquid coupling medium
between the crystal surface and the part surface is
necessary because:
A.279, 289-292; B.67
53.
a. lubricant is required to minimize wear on the
crystal surface.
b. an air interface between the crystal surface and
the part surface would almost completely reflect
the ultrasonic vibrations.
c. the crystal will not vibrate if placed directly in
contact with the surface of the part being
inspected.
d. the liquid is necessary to complete the electrical
circuit in the transducer.
B.11-13; G.37
54.
B.56
On the area-amplitude ultrasonic standard test
blocks, the flat-bottom holes in the blocks are:
a. all of the same diameter.
b. different in diameter, increasing by 0.4 mm
(0.016 in.) increments from the No. 1 block to the
No. 8 block.
c. largest in the No. 1 block and smallest in the
No. 8 block.
d. drilled to different depths from the front surface
of the test block.
Near-surface resolution is a characteristic of an
ultrasonic testing system that defines its ability to
detect:
a. discontinuities oriented in a direction parallel to
the ultrasonic beam.
b. discontinuities located in the center of a forging
containing a fine metallurgic structure.
c. minute surface scratches.
d. discontinuities located just beneath the
entry-surface in the part being tested.
All other factors being equal, the mode of vibration
that has the greatest velocity is the:
a. shear wave.
b. transverse wave.
c. surface wave.
d. longitudinal wave.
A.222-223
51.
During ultrasonic testing by the immersion method,
it is frequently necessary to angulate the transducer
when a discontinuity is located in order to:
B.104
55.
In immersion testing, verification that the transducer
is normal to a flat entry surface is indicated by:
a. maximum reflection from the entry surface.
b. elimination of water multiples.
c. proper wavelength.
d. maximum amplitude of the initial pulse.
A.279, 413
7
56.
A piezoelectric material can:
61.
a. convert a longitudinal beam to a shear wave.
b. convert a mechanical energy to electrical energy.
c. create ionization in a test specimen.
d. produce sound waves in a coaxial cable.
In immersion testing, the most commonly used
couplant is:
a. water.
b. oil.
c. glycerine.
d. alcohol.
A.60; B.76
B.62; E.222
57.
Sound waves of a frequency beyond the hearing
range of the human ear are referred to as ultrasonic
waves or vibrations, and the term embraces all
vibrational waves of frequency greater than
approximately:
62.
a. converts electrical energy into sound.
b. converts electrical energy into mechanical energy
and mechanical energy into electrical energy.
c. eliminates the signal-to-noise energy.
d. produces high-speed electrons in metals.
a. 2 kHz
b. 200 kHz
c. 20 000 Hz
d. 2 MHz
A.60; B.76
B.3; G.1
58.
63.
The velocity of sound waves is primarily dependent
on the:
B.4-5
A.36-37; G.38
B.37
When testing by the surface wave method, patches of
oil or dirt on the surface may:
a. block the progress of all sound.
b. attenuate the sound.
c. have no effect on the test.
d. cause both an attenuation of sound and
indications on the screen.
The angle of incidence is:
a. greater than the angle of reflection.
b. less than the angle of reflection.
c. equal to the angle of reflection.
d. not related to the angle of reflection.
A.38
65.
On many ultrasonic testing instruments, an operator
conducting an immersion test can remove that
portion of the display presentation that represents
water distance by adjusting a:
a. pulse length control.
b. reject control.
c. sweep delay control.
d. sweep length control.
A.183, 194, 262, 565
G.34
8
64.
The primary purpose of reference blocks is to:
a. aid the operator in obtaining maximum back
reflections.
b. obtain the greatest sensitivity possible from an
instrument.
c. obtain a common reproducible signal.
d. properly tune the transducer.
60.
The shortest wavelength pulse is produced by a
frequency of:
a. 1 MHz
b. 5 MHz
c. 10 MHz
d. 25 MHz
a. pulse length.
b. angle of incidence.
c. material properties and wave type.
d. frequency.
59.
The piezoelectric material in the transducer:
66.
What is another way to express 100 000 cycles per
second?
69.
Figure 7 is an illustration of a typical:
a. A-scan presentation.
b. B-scan presentation.
c. C-scan presentation.
d. D-scan presentation.
a. 0.1 kHz
b. 10 kHz
c. 100 kHz
d. 100 MHz
B.82; C.19
A.31-32; B.3
67.
Figure 5 is an illustration of a typical:
a. A-scan presentation.
b. B-scan presentation.
c. C-scan presentation.
d. D-scan presentation.
A.264; B.26-27; C.19
Figure 7.
70.
A transducer with a frequency greater than 10 MHz
will most likely be used during:
a. a straight beam contact test of aluminum ingot.
b. an angle beam contact test of a steel pipe.
c. a surface wave contact test of a metallic plate.
d. an immersion test.
Figure 5.
B.47
68.
Figure 6 is an illustration of a typical:
71.
a. A-scan presentation.
b. B-scan presentation.
c. C-scan presentation.
d. D-scan presentation.
The reference holes in standard aluminum
area-amplitude ultrasonic test blocks contain:
a. flat-bottom holes.
b. concave-surface holes.
c. convex-surface holes.
d. conical-shaped holes.
B.83; C.19
B.104
72.
The gradual loss of sonic energy as the ultrasonic
vibrations travel through the material is referred to
as:
a. reflection.
b. refraction.
c. reproducibility.
d. attenuation.
A.39; B.15
Figure 6.
9
73.
A term used to describe numerous small indications
on the instrument display resulting from test part
structure, numerous small discontinuities, or both is
often referred to as:
78.
The presence of a discontinuity will not produce a
specific discontinuity indication on the ultrasonic
instrument display when using the:
a. straight beam testing method.
b. surface wave testing method.
c. angle beam testing method.
d. through-transmission testing method.
a. multiple back reflections.
b. multiple front reflections.
c. grass or hash.
d. resonance.
A.230; B.64-65
B.195
79.
74.
When testing a plate, increasing the frequency of an
ultrasonic longitudinal wave results in:
The depth of a discontinuity cannot be determined
when using the:
a. straight beam testing method.
b. through-transmission testing method.
c. angle beam testing method.
d. immersion testing method.
a. an increase in its velocity.
b. a decrease in its velocity.
c. no change in its velocity.
d. a reversal in its velocity.
A.230
E.214
80.
75.
Ultrasonic waves transmitted into and received from
the test material in the form of repetitive bursts of
acoustic energy is called:
When inspecting coarse-grained material, a sound
wave is most easily scattered by the grain structure by
a frequency of:
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
a. pulse echo testing.
b. continuous wave testing.
c. resonance testing.
d. through-transmission testing.
A.409; B.47
A.202; B.64
81.
76.
Metal blocks, which contain one or more drilled
holes or notches to simulate discontinuities, are
called:
a. scrubbers.
b. crystal collimators.
c. single-plane angulators.
d. reference blocks.
a. 1 MHz transducer.
b. 5 MHz transducer.
c. 15 MHz transducer.
d. 25 MHz transducer.
B.47
82.
E.273; F.263
77.
The thickest crystal is contained in a:
If the major dimensions of a discontinuity in a
152 mm (6 in.) thick aluminum plate lie parallel to
the entry surface at a depth of 76 mm (3 in.), it will
be best detected by:
When performing a surface wave test, indications
may result from:
a. improper frequency.
b. oil on the surface.
c. a surface discontinuity.
d. the acoustical velocity of aluminum.
B.12-13
a. a straight beam test.
b. an angle beam test.
c. a surface wave test.
d. a lamb wave test.
B.91-92
10
83.
Which of the following discontinuities located 152
mm (6 in.) from the entry surface results in the
largest display indication if all factors except
discontinuity surface condition and orientation are
the same?
a. 2 mm (0.08 in.) diameter flat-surfaced
discontinuity whose major face is at an angle of
75° from the direction of sound beam
propagation.
b. 2 mm (0.08 in.) diameter rough-surfaced
discontinuity whose major face is at an angle of
75° from the direction of sound beam
propagation.
c. 2 mm (0.08 in.) diameter flat-surfaced
discontinuity whose major face is perpendicular
to the direction of sound beam propagation.
d. 2 mm (0.08 in.) diameter rough-surfaced
discontinuity whose major face is parallel to the
direction of sound beam propagation.
87.
A separate time baseline imposed on the viewing
display of some ultrasonic testing instruments that
permits measurement of distances is often referred
to as:
a. an initial pulse.
b. a time/distance line.
c. an electronic gate.
d. a sweep line.
A.180, 561
88.
A term used to describe the ability of an ultrasonic
testing system to distinguish between the
entry-surface response and the response of
discontinuities near the entry surface is:
a. sensitivity.
b. penetration.
c. segregation.
d. resolution.
B.148-149
84.
Transducers constructed with a plastic wedge or
standoff between the transducer element and the test
piece are commonly used:
B.56
89.
a. for angle beam contact testing.
b. for immersion testing.
c. to eliminate the need for a couplant.
d. to reduce the speed of electrons.
The phenomenon whereby an ultrasonic wave
changes direction when the wave crosses a boundary
between materials with different velocities is called:
a. refraction.
b. reflection.
c. penetration.
d. rarefaction.
B.81-88, 92
85.
Sound can be focused by special curved adapters
located in front of the transducer element. These
adapters are referred to as:
E.216
90.
a. scrubbers.
b. acoustic lenses.
c. angle beam adapters.
d. single plane adapters.
In a test where the transducer is not perpendicular
to the inspection surface, the angle of incidence is
equal to:
a. the angle of refraction.
b. the angle of reflection.
c. the shear wave angle.
d. half the shear wave angle.
A.95, 296-298
86.
A test method in which the parts to be inspected are
placed in a water bath or some other liquid couplant
is called:
a. contact testing.
b. immersion testing.
c. surface wave testing.
d. through-transmission testing.
A.262-263; B.66-68
F.235-236
91.
The product of the acoustic velocity of sound in a
material and the density of the material is the
factor that determines the amount of reflection or
transmission of ultrasonic energy when it reaches an
interface. This is called:
a. acoustic impedance.
b. velocity.
c. wavelength.
d. penetration.
E.234
11
92.
In transmitting energy into the part shown in
Figure 8, the ultrasonic beam will:
96.
a. diverge (spread out) through the part.
b. converge (focus in to a point) through the part.
c. transmit straight through the part.
d. not enter the part.
The formula used to calculate the angle of refraction
within a material is called:
a. Fresnel’s law.
b. Fraunhofer’s law.
c. Snell’s law.
d. Lamb’s law.
A.222
B.21-22; C.3
97.
Immersed
transducer
Convex
surface
In a material with a given velocity, when frequency is
increased, the wavelength will:
a. not be affected.
b. increase.
c. decrease.
d. double.
Test
specimen
B.5
98.
Figure 8.
93.
Circuits that electronically amplify return signals
from the receiving transducer and often modify the
signals into a form suitable for display are called:
a. pulser circuits.
b. marker circuits.
c. timer circuits.
d. receiver-amplifier circuits.
Ultrasonic waves that travel along the surface of a
material and whose particle motion is elliptical are
called:
F.253
a. shear waves.
b. transverse waves.
c. longitudinal waves.
d. rayleigh waves.
99.
a. an A-scan display.
b. a B-scan display.
c. a C-scan display.
d. an X-Y plot display.
A.39-40; B.12-13
94.
The most common type of data display used for
ultrasonic examination of welds is:
The interference field near the face of a transducer is
often referred to as the:
A. 182, 225, 264, 557
a. fresnel zone.
b. acoustic impedance.
c. exponential field.
d. phasing zone.
100.
B.23, 47-48; C.15-16
95.
When the incident angle is chosen to be between the
first and second critical angles, the ultrasonic wave
mode within the part will be a:
a. longitudinal wave.
b. shear wave.
c. surface wave.
d. lamb wave.
B.12, 21
12
The display that plots signal amplitude versus time is
called:
a. an A-scan display.
b. a B-scan display.
c. a C-scan display.
d. a D-scan display.
A.264; C.11-12
101.
A circuit that modifies the return signal from the
receiving transducer into a form suitable for display
on an oscilloscope or other output device is called a:
106.
What type of ultrasonic examination uses wheel-type
transducers that eliminate the use of a tank?
a. Through-transmission testing.
b. Contact testing.
c. Resonance testing.
d. Immersion testing.
a. pulser.
b. receiver-amplifier.
c. clock.
d. sweep.
A.99; B.67, 69, 70
A.69, 104; F.253
107.
102.
A circuit that generates a burst of voltage that is
applied to the sending transducer is called:
In addition to other functions, a transducer
manipulator in a mechanical immersion-scanning
unit permits:
a. a pulser.
b. a receiver-amplifier.
c. damping.
d. a clock.
a. use of the through-transmission technique.
b. use of high scanning speeds.
c. detection of obliquely oriented discontinuities.
d. utilization of less skilled operators.
A.69; F.252
103.
A circuit that coordinates electronic operation of the
entire ultrasonic instrument system is called:
A.267, 413
108.
a. damping.
b. a receiver-amplifier.
c. a clock.
d. a power supply.
A type of data presentation most likely to be used
with a high-speed automatic scanning system is:
a. an A-scan presentation.
b. a velocity versus amplitude plot.
c. a C-scan presentation.
d. a plot of echo height versus depth.
A.244; B.30, 79
104.
A plan view display or recording of a part under
examination is called:
A.264
109.
a. a C-scan display.
b. an A-scan display.
c. an X-axis plot.
d. a strip chart recording.
The component in a conventional immersion system
that spans the width of the immersion tank is called:
a. an articulator.
b. a bridge.
c. a manipulator.
d. a search tube.
A.264; C.19
105.
Ultrasonic data, which is presented in a form
representative of the cross section of the test
specimen, is called:
a. an A-scan presentation.
b. a B-scan presentation.
c. a C-scan presentation.
d. an X-Y plot.
A.193
110.
The component in an ultrasonic immersion system
that is used to adjust and maintain a known
transducer angle is called:
a. a carriage.
b. a manipulator.
c. a search tube.
d. an index system.
A.264; C.19
A.267, 413
13
111.
An amplitude type gate is necessary for all:
116.
a. shear wave examinations.
b. longitudinal wave examinations.
c. automatic examinations.
d. manual examinations.
Which material can only transmit longitudinal waves?
a. Machine oil.
b. Aluminum.
c. Ice.
d. Beryllium.
A.205
112.
When a C-scan recording is used to produce a
permanent record of an ultrasonic test, the
information displayed is typically the discontinuity’s:
B.11
117.
a. depth and size.
b. depth, orientation, and size.
c. location and depth.
d. location and size (plan view).
If the velocity of a longitudinal mode wave in a given
homogeneous material is 0.625 cm/μs at 13 mm
(0.5 in.) below the surface, what is the velocity at
51 mm (2 in.) below the surface?
a. One-fourth the velocity at 13 mm (0.5 in.).
b. One-half the velocity at 13 mm (0.5 in.).
c. The same as the velocity at 13 mm (0.5 in.).
d. Three-fourths the velocity at 13 mm (0.5 in.)
A.264
A.43
113.
Rough entry surface conditions can result in:
118.
a. an increase in echo amplitude from discontinuities.
b. a decrease in the width of the front-surface echo.
c. a loss of amplitude from discontinuities.
d. a loss of material velocity.
a. Make it longer.
b. Have no effect.
c. Make it shorter.
d. Increase it and the acousitc impedance.
A.204, 278
114.
As the grain size increases in a material, its principal
effect in ultrasonic testing is on the:
B.48
119.
a. velocity of sound.
b. attenuation.
c. acoustic impedance.
d. angle of refraction.
In straight beam pulse echo testing, a discontinuity
with a rough reflecting surface perpendicular to the
incident wave has what effect on the detected signal
in comparison to a smooth flat-bottom hole of the
same size?
a. It increases the detected signal.
b. It decreases the detected signal.
c. It has no effect on the detected signal.
d. It decreases the width of the pulse of the detected
signal.
A.195, 208
14
What can cause nonrelevant indications on the
A-scan display?
a. Rectangular-shaped test specimens.
b. Setting a low pulse repetition rate.
c. Small grain structure of test specimens.
d. Edge effects.
A.211
115.
What effect will replacing a 2.25 MHz transducer
with a 5 MHz transducer have on the wavelength?
A.277, 278
120.
The proper interpretation and evaluation of the
presented discontinuity signals are essential to any
nondestructive test. A common method for the
estimation of discontinuity size is the use of:
a. a double transducer test.
b. a piezoelectric standard.
c. mode conversion.
d. a reference standard.
A. 206
121.
Another name for fresnel zone is:
126.
a. zone.
b. near field.
c. far field.
d. torrid zone.
An A-scan display, which shows a signal both above
and below the sweep line, is called:
a. a video display.
b. an RF display.
c. an audio display.
d. a frequency modulated display.
B.23, 47; C.5, 15
A.87; B.81
122.
Attenuation is a:
127.
a. test display characteristic.
b. test material parameter.
c. transducer characteristic.
d. form of testing.
a. distance a discontinuity is from the transducer
and its through-dimension thickness.
b. distance a discontinuity is from the transducer
and its length in the direction of transducer
travel.
c. cross-sectional area of a discontinuity above a
predetermined amplitude.
d. pulse height and time of arrival to produce a
plan-view image.
B.15, 164
123.
A B-scan display shows the relative:
For discontinuity geometries other than flat, the echo
amplitude is usually _________ from that observed
for a flat discontinuity, of similar orientation
perpendicular to the sound beam.
A.180-181; B.27-28
a. identical
b. increased
c. decreased
d. elongated
128.
a. are not reflected from a sharp edge corner.
b. are reflected from a sharp edge corner.
c. travel through the sharp edge corner and are
reflected from the lower edge.
d. are absorbed by a sharp edge corner.
A.195, 309-310
124.
To evaluate discontinuities that are oriented at an
angle to the entry surface so that the sound beam
strikes the plane of the discontinuity at right angles,
the operator must:
a. change the frequency.
b. grind the surface.
c. angulate the transducer.
d. increase the gain.
B.12-13
129.
The pulser circuit in an ultrasonic instrument is used
to:
a. control the horizontal and vertical sweep.
b. activate the transducer.
c. control transducer timing between transmit and
sweep.
d. generate markers that appear on horizontal
sweep.
A.182; B.79
Surface (rayleigh) waves are more highly attenuated
by a:
a. curved surface.
b. heavy couplant.
c. thin couplant.
d. sharp corner.
B.52, 96
125.
Surface (rayleigh) waves traveling on the top face of a
block:
B.12-13, 63
130.
The velocity of sound in a material is dependent
upon the:
a. frequency of the wave.
b. wavelength.
c. material properties.
d. vibration cycle.
A.309
15
131.
To vary or change the wavelength of sound being
used to test a part, change the:
136.
a. sound wave frequency.
b. diameter of the transducer.
c. electrical pulse voltage.
d. pulse repetition rate.
a. four times the test piece thickness.
b. one-half the test piece thickness.
c. one-fourth the test piece thickness plus 6 mm
(0.25 in.).
d. one-half the test piece thickness plus 6 mm
(0.25 in.)
B.5
132.
Longitudinal wave velocity in water is approximately
one-fourth the velocity in aluminum or steel.
Therefore, the minimum water path should be:
Ultrasonic vibrations are commonly used to:
A.262; F.258
a. support findings after visual inspection.
b. characterize grain structure.
c. detect discontinuities in multilayered structures
having air gaps between layers.
d. perform volumetric examinations of ferrous and
nonferrous materials.
137.
a. adjust the viscosity.
b. help eliminate the formation of air bubbles.
c. prevent cloudiness.
d. aid in technician comfort.
B.1, 2
133.
Which of the following has the longest fresnel zone?
a. 13 mm (0.5 in.) diameter 1 MHz.
b. 13 mm (0.5 in.) diameter 2.25 MHz.
c. 28.5 mm (1.125 in.) diameter 1 MHz.
d. 38 mm (1.5 in.) diameter 2 MHz.
B.62
138.
The formula used to determine the fundamental
resonant frequency is:
a. F = V/T.
b. F = V/2T.
c. F = T/V.
d. F = VT.
A.210; B.47-48
134
In immersion testing, a wetting agent is added to the
water to:
When contact testing, if the ultrasonic instrument is
set with an excessively high pulse repetition
frequency:
A.478
139.
a. the screen trace becomes too light to see.
b. the time-baseline becomes distorted.
c. the initial pulse disappears.
d. UT signals may overlap with the multiples of the
backwall echoes.
If frequency is increased, wavelength:
a. decreases (becomes shorter).
b. increases (becomes longer).
c. remains the same but velocity increases.
d. remains the same but velocity decreases.
A.187
135.
The advantages of immersion testing include:
B.5
140.
a. portability.
b. reduced equipment needed.
c. low equipment and maintenance costs.
d. adaptability for automated scanning.
F.258
The variable in distance amplitude calibration block
construction is the:
a. drilled hole size.
b. drilled hole point angle.
c. metal distance above the drilled hole.
d. angle of the drilled hole to block longitudinal
axis.
B.39-40, 105-106; F.264
16
141.
When setting up a distance amplitude correction
curve using three flat-bottom holes, sometimes the
hole closest to the transducer gives less of a response
than one or both of the other two. This could be
caused by:
a. a hole that is too large.
b. near field effects.
c. impedance mismatch.
d. the acoustic velocity.
146.
a. increases.
b. decreases.
c. stays the same.
d. cannot be determined.
B.18-20
147.
F.239, 263
142.
Ferrous and nonferrous welds may be ultrasonically
tested using a frequency range of:
Both longitudinal and shear waves may be
simultaneously generated in a second medium when
the angle of incidence is:
a. between normal and the first critical angle.
b. between the first and second critical angles.
c. past the second critical angle.
d. only at the second critical angle.
a. 25-100 kHz
b. 200-500 kHz
c. 2-5 MHz
d. 3-6 MHz
B.21
The product of the material density and the velocity
of sound within that material is referred to as:
Penetration of ultrasonic waves in a material is
normally the function of test frequency used. The
greatest depth of penetration is provided by a
frequency of:
a. acoustic impedance.
b. near field.
c. acoustic attenuation.
d. ultrasonic beam distribution.
a. 1 MHz
b. 2.25 MHz
c. 5 MHz
d. 10 MHz
A.226
143.
For a given incident angle, as the frequency of the
transducer increases, the refracted angle:
148.
B.15
144.
A straight beam contact transducer consists of:
B.47
149.
a. a case, a crystal, wear plate, and backing.
b. a case, a crystal, backing, and a plastic wedge.
c. a case, a crystal, backing, and acoustic lenses.
d. a case, a crystal, a mount, backing, a plastic
wedge, and acoustic lenses.
Refracted energy assumes a new direction of
propagation when the _________ is changed.
a. principal angle
b. reflected angle
c. critical angle
d. incident angle
B.45
145.
In immersion testing, to remove the second water
reflection from between the entry surface signal and
the first back reflection, you should:
B.19-21
150.
The loss of energy as it propagates through material
is the result of beam:
a. interference.
b. attenuation.
c. absorption.
d. reflection.
a. increase the repetition rate.
b. decrease the frequency.
c. decrease the sweep length.
d. increase the water path.
B.15
B.68
17
151.
In selecting a suitable couplant, which of the
following characteristics would not affect the
selection?
156.
A device that transforms electrical pulses into
mechanical and vice versa utilizes:
a. Snell’s law.
b. piezoelectric principles.
c. mode conversion principles.
d. particle motion principles.
a. Mode of propagation desired.
b. Material surface finish and temperature.
c. Operating frequency of the transducer.
d. Chemical properties of the couplant.
B.45
B.61
157.
152.
Excessive surface roughness of the material being
tested can cause:
a. the refracted wave is mode converted.
b. the refracted wave is the same mode as the
incident wave.
c. the refracted wave in steel has two components,
one of which will be the same mode as the
incident wave.
d. it is impossible to determine mode(s) of a
refracted wave without more information.
a. a loss of echo amplitude from discontinuities
within the material.
b. reduced acoustic velocity.
c. increased acoustic velocity.
d. increased back-surface response.
B.54
153.
Reference or calibration standards are used for:
B.19
a. determining phase shift analysis.
b. providing a method for standardizing the test
system.
c. determining tensile strength.
d. measuring vibrations.
158.
The change in direction of an ultrasonic beam when
it passes from one material to another material in
which elasticity and density differ is called:
a. reflection.
b. rarefaction.
c. angulation.
d. refraction.
F.239, 263
B.18
155.
If a discontinuity is located in the fresnel or near-field
region of a sound beam:
a. the larger the discontinuity, the larger the
amplitude of the reflected signal.
b. the closer to the surface the discontinuity is
located, the larger will be the amplitude of the
reflected signal.
c. in immersion testing, the amplitude of the signal
increases as the water path decreases.
d. in immersion testing, the amplitude of the
reflected signal may increase or decrease as the
water path decreases.
B.37, 101
154.
Whenever an ultrasonic incident angle is set at 5°
from normal in water:
If a discontinuity is oriented at an angle other than
90° to the sound beam, the results may be a:
a. loss of signal linearity.
b. loss or lack of signal reflected from the
discontinuity.
c. focusing of the sound beam.
d. loss of interference phenomena.
B.148-149
159.
If a transducer is vibrating at a frequency and
injecting ultrasonic energy through water into a steel
specimen:
a. the sound wavelength is the same in both the
water and the steel.
b. the sound frequency in the water is less than the
sound frequency in steel.
c. the sound wavelength is not the same in both the
water and the steel.
d. the sound frequency in the water is greater than
the sound frequency in steel.
A.43
18
160.
When a longitudinal sound wave strikes a watersteel interface at an angle of incidence of 15°
(see Figure 9):
a. all the sound energy is reflected back into the
water at an angle of 15°.
b. part of the sound energy is reflected at 15° and
part is refracted into the steel at an angle of less
than 15°.
c. part of the sound energy is reflected at 15° and
part is refracted along the water-steel interface.
d. part of the sound energy is reflected at 15° and
part is refracted into the steel at an angle greater
than 15°.
15°
Figure 9.
B.19-20
Answers
1d
2a
15d 16a
29a 30c
43c
44c
57c
58c
71a
72d
85b 86b
99a 100a
113c 114b
127b 128b
141b 142c
155b 156b
3c
17b
31c
45c
59c
73c
87c
101b
115b
129b
143a
157c
4b
18d
32c
46a
60d
74c
88d
102a
116a
130c
144a
158d
5c
19b
33c
47a
61a
75a
89a
103c
117c
131a
145d
159c
6d
20d
34a
48a
62b
76d
90b
104a
118c
132d
146c
160d
7b
21a
35b
49a
63d
77a
91a
105b
119d
133d
147a
8c
22b
36c
50b
64c
78d
92a
106d
120d
134d
148a
9d
23a
37a
51d
65c
79b
93d
107c
121b
135d
149d
10b
24b
38b
52b
66c
80d
94a
108c
122b
136c
150b
11d
25b
39c
53d
67a
81a
95b
109b
123c
137b
151c
12d
26c
40a
54b
68c
82c
96c
110b
124c
138b
152a
13a
27d
41a
55a
69b
83c
97c
111c
125b
139a
153b
14c
28b
42b
56b
70d
84a
98d
112d
126b
140c
154d
19