UT 2 - Test Questions Flashcards by Jamie Garrah

Mechanical wave motion requires;

a) high pressure
b) low pressure
c) particle motion
d) ionic bonding and disbonding

c) particle motion

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In a homogeneous and isotropic elastic medium such as low carbon steel, sound velocity;

a) decreases with distance from source
b) varies with direction
c) is constant in all directions
d) depends on frequency

c) is constant in all directions

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The amount of time between two compressions, or two rarefactions of an elastic wave is called;

a) wavelength
b) period
c) frequency
d) velocity

b) period

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The velocity of sound;

a) is constant for all materials.
b) varies with frequency.
c) varies inversely with wavelength.
d) is a characteristic of the material.

d) is a characteristic of the material.

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Compared to the atomic or molecular spacing of a material, ultrasonic wavelengths are;

a) much greater
b) smaller
c) about the same distance
d) are multiples of the atomic spacing

a) much greater

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The elastic wave that has particle motion parallel to the direction of wave propagation is called;

a) longitudinal wave
b) compression wave
c) density wave
d) all of the above

d) all of the above

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In Rayleigh waves, particle motion is;

a) parallel to the direction of wave propagation
b) right angles to the direction of wave propagation
c) retrograde
d) in counter-clockwise ellipses

d) in counter-clockwise ellipses

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Rayleigh waves can be used in steel to penetrate up to;

a) 10mm
b) 10cm
c) 1m
d) 1 wavelength

d) 1 wavelength

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CHECK/EDIT

In bending waves (plate wave mode) particles in the middle zone of the plate vibrate;

a) in longitudinal mode
b) in shear mode
c) in Rayeigh mode
d) not at all

b) in shear mode

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In the Lamb wave, called a dilational wave, particles in the middle zone of the plate vibrate;

a) in longitudinal mode
b) in shear mode
c) in Rayleigh mode
d) not at all

a) in longitudinal mode

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If one sound beam passes through another moving in the opposite direction, the result will be;

a) a change in amplitude
b) a change in direction
c) a change in frequency
d) no change

a) a change in amplitude

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In a standing wave, nodes and antinodes are separated by;

a) 1/4 wavelength
b) 1/2 wavelength
c) 1 wavelength
d) 2 wavelengths

a) 1/4 wavelength

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Standing waves are generated in ultrasonic testing for;

a) through testing (pitch-catch)
b) resonance thickness testing
c) flaw detection
d) B-scans

b) resonance thickness testing

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Specific acoustic impedance, is the product of;

a) density and permittivity
b) hardness and velocity
c) velocity and density
d) specific activity and amplitude

c) velocity and density

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Poisson’s ratio is expressed in units of;

a) m/s
b) Pa
c) N/m2
d) no units, it is dimensionless

d) no units, it is dimensionless

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Frequency can be expressed in terms of;

a) 1/s (s=seconds)
b) cps
c) Mhz
d) all of the above

d) all of the above

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The ratio of sound velocity in water to the longitudinal velocity of sound in steel is very nearly;

a) 1:1
b) 1:2
c) 1:4
d) 1:5

c) 1:4

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Rayleigh wave velocities for a given material are always;

a) greater than longitudinal wave velocities
b) greater than transverse wave velocities
c) less than transverse wave velocities
d) about the same as shear wave velocities

c) less than transverse wave velocities

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The ratio of the incident sound pressure to the reflected sound pressure is called the;

a) acoustic impedance
b) acoustic intensity
c) coefficient of reflection
d) coefficient of transmission

c) coefficient of reflection

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The ratio of the incident sound pressure to the transmitted sound pressure is called the;

a) acoustic impedance
b) acoustic intensity
c) coefficient of reflection
d) coefficient of transmission

d) coefficient of transmission

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When is the coefficient of transmission a negative value?

a) if Z incident is less than Z transmitted
b) If Z incident is greater than Z transmitted
c) if Z incident equals Z transmitted
d) never

d) never

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Incident sound pressure plus reflected sound pressure equals;

a) 0
b) 1
c) transmitted sound pressure
d) none of the above

c) transmitted sound pressure

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Total incident sound intensity can be calculated from;

a) the sum of the reflected and transmitted intensities
b) the difference between reflected and transmitted intensities
c) R plus D (reflection and transmission coefficients)
d) R minus D (reflection and transmission coefficients)

a) the sum of the reflected and transmitted intensities

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(Sin a1) (C2) = (Sin a2) C1) is a form of;

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

b) Snell’s law

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If the Sine of a refracted angle is calculated to be 0.707, the refracted angle will be equal to; a) 36 degrees b) 45 degrees c) 60 degrees d) undetermined from the given information

b) 45 degrees

For a shear wave travelling from steel to water incident on the boundary at 10 degrees will give a refracted shear wave in water with an angle of; a) 0 degrees b) 5 degrees c) 20 degrees d) none of the above

d) none of the above

The critical angle refers to the; a) longitudinal wave angle b) incident angle c) refracted angle d) reflected shear wave

b) incident angle

The critical angle occurs when the sine of the refracted angle equals; a) 0.707 b) 0.846 c) 1.000 d) 1.414

c) 1.000

At a solid to a free boundary (air), an obliquely incident longitudinal wave from the solid can result in, at most; a) a reflected longitudinal wave only b) a reflected longitudinal and a reflected shear wave c) a refracted longitudinal long wave d) a reflected longitudinal, a reflected shear and a refracted longitudinal wave

b) a reflected longitudinal and a reflected shear wave

At a liquid/solid boundary with an obliquely incident longitudinal wave from the liquid, result could be at most; a) a reflected longitudinal wave only b) a refracted longitudinal wave only c) a reflected longitudinal, and a refracted long wave d) a reflected long, a refracted long and a refracted shear wave

d) a reflected long, a refracted long and a refracted shear wave

Given the velocity of water = 1.5 mm/us and the longitudinal velocity for steel = 5.9 mm/us; what is the second critical angle of an incident longitudinal wave from steel into water? a) 19 degrees. b) 27 degrees. c) 36 degrees. d) none of the above.

d) none of the above.

A shear wave polarized in the plane of incidence impinging on a free boundary at right angles to the boundary will result in; a) a reflected shear wave only b) a reflected shear wave and a reflected longitudinal wave c) a reflected longitudinal wave only d) a surface wave

a) a reflected shear wave only

Maximum surface wave energy is obtained when the angle of incidence is; a) 0 degrees b) 60 degrees c) 90 degrees d) just over the critical angle

d) just over the critical angle

Geometric-optic treatment of ultrasonic waves fails to account for; a) reflection b) refraction c) diffraction d) normal incidence

c) diffraction

The relationship for acoustic pressure of spherical waves P=Pe/d, implies; a) an inverse proportionality to distance b) infinite sound pressure at the source c) both a and b d) none of the above

c) both a and b

Spherical and cylindrical waves reflecting off a plane surface preserve shape but not; a) velocity b) wavelength c) frequency d) acoustic pressure distribution

d) acoustic pressure distribution

The advantage of inspecting a thick solid cylinder with a waterpath two times the cylinder radius instead of just the cylinder radius is; a) increased sensitivity b) reduced entry noise c) smaller near zone d) more uniform pressure through the cylinder

d) more uniform pressure through the cylinder

CHECK The ratio of the diameter of an oscillator to the wavelength it generates gives the; a) acoustic velocity b) near zone length c) acoustic impedance of the oscillator d) number of interference maxima and minima

d) number of interference maxima and minima

WRONG For practical purposes, the equation for the near zone distance can be approximated by (where l = wavelength and D = probe diameter) a) D / l b) D squared / 4 l c) D squared minus l squared/4 l d) (D-4l)/l squared

b) D squared / 4 l

Given an "X-cut" normal beam contact probe on steel, the probe is 12 mm diameter and has a frequency of 2 MHz. The approximate near zone length is (V steel = 6.0mm/us) a) 4mm b) 12mm c) 24mm d) 48mm

b) 12mm

A transducer has a near field in water of 35 mm. When used in contact on steel the near zone will be about; a) 47 mm b) 35 mm c) 18 mm d) 9 mm

d) 9 mm

The angle of divergence applies to the; a) dead zone b) near field c) Fresnel zone d) far field

d) far field

CHECK Sin(gamma) = 1.2 lambda / D (where lambda is wavelength and D is the crystal diameter) is the equation for; a) the first critical angle b) interference minima in the near zone c) half angle of divergence in the Fraunhoffer zone d) optimum energy angle for shear waves

c) half angle of divergence in the Fraunhoffer zone

The angle of divergence is a function of; a) crystal thickness of the probe b) crystal dimensions c) crystal shape d) all of the above

d) all of the above

A rectangular probe, 4mm X 8mm, will have its maximum half angle of divergence; a) in the 4mm direction b) in the 8mm direction c) in no particular orientation d) constant in all directions

a) in the 4mm direction

Given a 10 X 10mm square probe of 5 MHz fundamental frequency, compared to a 10mm diameter 5 Mhz probe, the near zone of the square probe would be; a) longer b) shorter c) the same d) independent of wavelength

a) longer

In ultrasonic testing, actual point focusing of sound is not possible due to; a) damping effects b) divergence in the far zone c) asymetric vibrations d) diffraction effects

d) diffraction effects

CHECK Huygen's wavelet theory and Fresnel zones can be used to predict; a) focal length b) maxima and minima points in a sound beam c) radius of curvature in a focused probe d) fundamental frequency

b) maxima and minima points in a sound beam

AVG (or DGS in English) diagrams compare flaw signal amplitudes to; a) side drilled holes b) flat bottomed holes c) a theoretical maximum d) DAC's

c) a theoretical maximum

Flaws oriented obliquely to the incident sound beam may be better detected using; a) high gain b) higher frequency c) focused probes d) separate transmit and receive probes

d) separate transmit and receive probes

Echo amplitudes of reference reflectors are dependant on; a) size b) shape c) wave mode d) all of the above

d) all of the above

A surface can be considered smooth if its irregularities are not more than ________ wavelength. a) 1 b) 1/3 c) 1/10 d) 1/100

b) 1/3

The problem of scatter off a rough surface can be reduced by; a) immersion testing b) a smaller diameter probe c) a lower frequency probe d) longer pulse length

c) a lower frequency probe

The effect of oxides or other non-metallic inclusions within a defect is to; a) amplify the signal b) split the signal by mode conversion c) reduce the signal amplitude d) none of the above

c) reduce the signal amplitude

As the pulse length of the excitation voltage is shortened, the transmitted pulse; a) frequency spectrum broadens b) frequency spectrum shortens c) increases energy output d) increases penetration ability

a) frequency spectrum broadens

In general, the frequency content of an ultrasound beam has a larger proportion of high frequencies in its spectrum; a) on axis b) off axis c) in the far zone d) in the free zone

a) on axis

The most significant result of scatter and absorption is; a) frequency content changes b) directivity c) attenuation d) beam spreading

c) attenuation

The effect of attenuation by absorption is most pronounced; a) in steel b) on the beam axis c) on higher frequencies d) on lower frequencies

c) on higher frequencies

A neper (Np) is a unit of; a) attenuation b) acoustic impedance c) pulse rate d) wavelength

a) attenuation

If 3dB were removed from a 100% FSH signal the resulting signal would be __________ FSH. a) 97 b) 94 c) 85 d) 71

d) 71

If a signal is dropped from 100% FSH to 32% FSH, the number of dB gain removed from the receiver is; a) 14 b) 10 c) 6 d) 4

b) 10

Attenuation in plastics and rubber is predominantly attributable to; a) absorption b) scatter c) beam spread d) none of the above

a) absorption

The attenuation coefficient has the units; a) dB/m b) Np/cm c) Np/mm d) all of the above

d) all of the above

Non-crystallized materials such as glass are most likely to be; a) isotropic b) anisotropic c) piezoelectric d) not inspectable

a) isotropic

CHECK Attenuation in cast metals is usually reduced by; a) forging b) rolling c) extruding d) all of the above

d) all of the above

For a given metal of a given grain size, attenuation in the cast form of the metal relative to the worked form is usually; a) greater b) less c) identical d) unpredictable

a) greater

The effect utilized by ultrasonic transducer crystals is the _________ effect. a) piezoelectric b) pyroelectric c) ferroelectric d) hall

a) piezoelectric

A piezoelectric crystals' structure will always contain; a) face-centered cubic form b) hexagonal form c) symmetry about polar axes d) asymmetry about polar axes

d) asymmetry about polar axes

An X-cut quartz crystal is primarily used to generate the ________ wave mode. a) longitudinal b) transverse c) Rayleigh d) Lamb

a) longitudinal

A typical voltage range for driving (exciting) piezoelectric crystals would be; a) 50 to 100 mV b) 50 to 100 V c) 50 to 100 kV d) 500 to 1000 V

d) 500 to 1000 V

Y-cut crystals generate shear waves into a solid material by; a) refraction b) direct coupling c) reflection d) no means known

b) direct coupling

The efficiency of the piezoelectric effect is rated by K33 which is the; a) piezoelectric modulus b) electromechanical coupling factor c) deformation constant d) Young's modulus

b) electromechanical coupling factor

After a voltage excitation of the piezoelectric crystal, the amplitude of its oscillations decrease by a quantity which is determined by the; a) Q factor b) damping coefficient c) characteristic frequency d) resonance frequency

b) damping coefficient

The characteristic or fundamental frequency of a piezoelectric material is not dependent on; a) damping material on either face b) thickness of crystal c) velocity of sound in the crystal d) all of the above

a) damping material on either face

To determine the damping coefficient you must know; a) the acoustic impedance of the backing material b) the acoustic impedance of the loading (front) material c) both a and b d) none of the above

c) both a and b

Harmonic resonances of piezoelectrically excited crystals occur at: a) twice the characteristic frequency. b) all even multiples of the first resonant frequency. c) all odd multiples of the first resonant frequency. d) none of the above.

c) all odd multiples of the first resonant frequency.

Although rarely used in modern day NDT transducers, quartz has the advantage of; a) chemical inertness b) high coupling coefficient c) high dielectric constant d) all of the above

a) chemical inertness

For high temperature measurements, the preferred piezoelectric material is; a) lithium niobate b) lithium sulphate hydrate c) quartz d) PZT

a) lithium niobate

Polarization of PZT crystals is accomplished using; a) strong permanent magnets b) strong alternating voltage c) strong direct voltage d) none of the above

c) strong direct voltage

A significant disadvantage of PZT as a transducer material is its; a) low density b) high curie point c) high acoustic impedance preventing good matching d) exceptionally high electromechanical coupling coefficient

c) high acoustic impedance preventing good matching

Electrodynamic methods of generating and receiving ultrasound rely on; a) magnetrostriction b) eddy currents c) laser heating d) none of the above

b) eddy currents

Magnetostricitive probes consist of; a) copper windings through thin laminated plates b) copper windings around a ceramic core c) solid steel wrapped with copper wire d) none of the above

a) copper windings through thin laminated plates

Optical methods used in ultrasonic testing such as Schlieren diffraction and interferometer methods are used in; a) transmission techniques only b) reception techniques only c) both transmission and reception d) optical methods are not used in ultrasonics

b) reception techniques only

To make useful ultrasonic holograms, requires; a) penetrating acoustic waves b) a source of reference waves c) conversion means to optical holograms d) all of the above

d) all of the above

CHECK Pulse-echo ultrasonic testing; a) uses a single probe b) uses separate transmitter and receiver probes c) both a and b d) none of the above

c) both a and b

Using the pulse echo method with a 0 degree probe, having separate transmit and receive crystals, the pattern on a CRT of a flat steel plate would appear as; a) evenly spaced multiples. b) randomly spaced multiples. c) a single spike from the opposite wall. d) an uninterrupted base line.

a) evenly spaced multiples.

Phantom echoes of multiples when testing thick specimens are a result of; a) insufficient suppression b) modulation from the power supply c) PRF set too high d) too much gain

c) PRF set too high

The initial pulse is formed as a result of the; a) dead zone b) couplant/specimen interface c) transmitter pulse d) all of the above

c) transmitter pulse

When an ultrasonic machine is equipped with this option, the pulse energy and pulse length can be adjusted by the; a) receiver fine grain control b) swept gain c) time corrected gain d) damping

d) damping

The voltage of a received ultrasonic signal at the machine's receiver is typically; a) 1/1000 to 1 volt b) 10 to 100 volts c) 100 to 1000 volts d) not measurable

a) 1/1000 to 1 volt

In order to adequately amplify received signals an ultrasonic machine's receiver amplifier must have a gain of about; a) 6 to 12 dB b) 20 to 40 dB c) 80 to 100 dB d) 100 to 200 dB

c) 80 to 100 dB

The main disadvantage of a broadband receiver in a ultrasonic machine is; a) non-linear response to amplification b) amplifier noise limits possible amplification c) RF display cannot be used d) rectified display cannot be used

b) amplifier noise limits possible amplification

The zero time on a contact normal beam probe; a) corresponds to the rising edge of the main bang b) corresponds to the falling edge of the main bang c) is determined indirectly by calibration blocks d) none of the above

c) is determined indirectly by calibration blocks

The acoustic impedance of backing material is often increased by; a) adding a tuning transformer to the probe b) increasing test pressures c) adding metal powder to the material d) increasing suppression

c) adding metal powder to the material

A great disadvantage of the old quartz crystal transducers that used the work piece as one of the electrodes was; a) a fluctuating dead zone b) insufficient damping c) decreasing sensitivity with use d) an increase in frequency with use

d) an increase in frequency with use

A contact angle beam probe used in fixed housings occasionally requires; a) transformer tuning b) machining or replacing of the wear face c) new couplant between crystal and plastic wedge d) all of the above

b) machining or replacing of the wear face

Wedges used to introduce refracted waves into a test specimen are made of; a) copper b) brass c) plastics d) all of the above can be used

d) all of the above can be used

In order that one can operate above the critical angle of reflection of longitudinal waves, wedge material for angle beams are; a) grooved on the front face b) always made of polystyrene c) chosen with a longitudinal velocity greater than the shear velocity of the test piece d) chosen with a longitudinal velocity less than the shear velocity of the test piece

d) chosen with a longitudinal velocity less than the shear velocity of the test piece

The layer of highly absorbing material sometimes bonded to the top and front of an angle probe's wedge is called a (an); a) cap b) backing c) anechoic trap d) none of the above

c) anechoic trap

A calibration for horizontal linearity would check properties of the; a) receiver amplifier b) image unit (oscilloscope) c) calibration block d) probe

b) image unit (oscilloscope)

The purpose of the 50mm diameter perspex insert in the IIW block is to; a) check constancy of probe sensitivity b) establish probe exit point c) calibrate for range d) both a and b

d) both a and b

An echo pulse width determines; a) a system's resolving power b) time of flight c) the far zone length d) the frequency of the probe

a) a system's resolving power

Pulse echo instruments without an image tube are; a) not useful in NDT b) not yet available c) used for wall thickness measurements d) not portable

c) used for wall thickness measurements

Electronic gates on the trace of a UT machine can be used to; a) determine the presence of flaws b) determine the amplitude of flaws c) both a and b d) none of the above

c) both a and b

When flaw echo signals are recorded so as to display a plan view of the test piece the presentation is called; a) A-scan b) B-scan c) C-scan d) D-scan

c) C-scan

Resonance testing techniques, as used for determining thickness, use; a) continuous sound waves b) pulsed sound waves c) Y-cut quartz crystal transducers d) all of the above

a) continuous sound waves

The purpose of a reference delay-line in an ultrasonic interferometer is for; a) determining amplitude from a known reflector b) accurate time measurements c) eliminating near zone effects d) eliminating dead zone effects

b) accurate time measurements

Uniform and strongly adhering films of paint or oxides are not removed for ultrasonic testing if; a) sand blasting cannot remove them b) formed on curves surfaces c) their presence does not interfere with the test d) sufficiently smooth

c) their presence does not interfere with the test

Due to its cost and toxicity _________ is not used as a couplant in contact testing; a) SAE oil b) heavy diesel oil c) mercury d) methyl-cellulose solution

c) mercury

Water jet techniques with water paths of 100mm are restricted to the through transmission methods because; a) sound cannot travel upstream for pulse-echo testing b) too much water is required c) of disturbing echoes behind the surface echo d) none of the above

c) of disturbing echoes behind the surface echo

A narrow high intensity ultrasound beam capable of finding very small flaws has its disadvantage in; a) sizing the flaw b) characterizing the flaw c) requiring a small scanning grid d) none of the above

c) requiring a small scanning grid

An effective maximum range for a 5MHz 10mm diameter probe is around ________ in steel. a) 50mm b) 100mm c) 200mm d) 300mm

b) 100mm

CHECK A minimum distance of a probe from an edge of the test piece is maintained to eliminate side wall interference. This distance is inversely proportional to the; a) sound path b) wavelength c) frequency d) beam spread

c) frequency

When testing a 30mm diameter, 500 mm long shaft from the flat end of the shaft using longitudinal waves from a 20 mm diameter 2 MHz probe, numerous signals are seen on the screen after 500mm. These are; a) ghost images b) secondary echos c) internal thread indications d) none of the above

b) secondary echos

Touching the reflection point of a normally incident transverse wave with an oily finger will; a) reduce the signal by about 2 dB b) reduce the signal by about 6 dB c) increase the signal by about 2 dB d) have no effect on signal amplitude

d) have no effect on signal amplitude

WRONG When using a refracted angle of 60 degrees on a 20mm thick plate the half skip distance is; a) 28mm b) 34mm c) 40mm d) 58mm

c) 40mm

To calculate skip distance in a flat plate of thickness 'd' for a refracted angle 'X' we use the formula; a) (cos X)/d b) (sin 2X)/d c) 2d/cos X d) 2d (tan x)

d) 2d (tan x)

To inspect cylindrical pieces with transverse waves in the circumferential direction, maximum depth is obtained using; a) 35° refracted angle b) 45° refracted angle c) 70° refracted angle d) any of the above is adequate if the diameter ratio is sufficient

d) any of the above is adequate if the diameter ratio is sufficient

The delta technique is used to determine; a) flaw size b) wall thickness c) flaw orientation d) all of the above

c) flaw orientation

Surface waves used for ultrasonic testing are generated by; a) conversion of longitudinal waves via plastic wedges b) Y-cut quartz crystals c) both a and b d) surface waves are not used in ultrasonic testing

c) both a and b

Frequency analysis of the reflected pulse is occasionally used to determine; a) flaw size b) flaw depth c) coupling efficiency d) wave velocity

a) flaw size

Changes in flaw echo shape on the video display are used to determine; a) flaw depth b) flaw type c) stand-off d) all of the above

b) flaw type

A defect that is not likely to be located by ultrasonic testing of a forging blank is; a) segregation b) flake cracks c) non-metallic inclusions d) cold cracks

a) segregation

In order to introduce a shear mode into cylindrical shaped specimens when immersion scanning in the circumferential direction you need to; a) use Y-cut crystals in the transducer b) switch from pulse-echo to through transmission c) off-set the probe from normal incidence d) none of the above

c) off-set the probe from normal incidence

When immersion inspecting small diameter tubing (<15mm diameter) with a normal beam probe radiating axially towards a mirror mounted ahead of it, the wave mode used for inspection in the tube is; a) longitudinal b) transverse c) either a or b depending on mirror orientation d) none of the above, mirrors are not used

c) either a or b depending on mirror orientation

Below 20 kHz, sound waves are considered to be; a) ultrasonic b) sonic c) subsonic d) infra-sonic

b) sonic

Relatively low ultrasonic frequencies are used in long range sonar units because; a) whales and submarines are big targets b) higher frequencies cause whales to attack c) sea water attenuates sound at 60 dB/km d) all of the above

c) sea water attenuates sound at 60 dB/km

Lamb waves are used in testing; a) thin bar or plate b) composite materials c) liquids d) bolts

a) thin bar or plate

The time required for a wave packet of ultrasound to go from 10% to 90% of its maximum amplitude is called; a) pulse length b) PRF c) rise time d) fall time

c) rise time

The time duration for an ultrasonic wave packet to have its trailing edge drop from 90% to 10% of its maximum amplitude is called; a) pulse length b) PRF c) rise time d) fall time

d) fall time

CHECK Ferroelectric materials are electrostrictive substances that exhibit; a) low acoustic impedance b) high coupling coefficients c) large deformations with applied voltage d) natural acoustic damping properties

c) large deformations with applied voltage

In ferroelectric materials, the units which contain a net electric polarization are called; a) cells b) bi-poles c) mono-poles d) domains

d) domains

A voltage applied across a slice of piezoelectric material will cause it to; a) twist b) expand c) contract d) either b or c depending on polarity

d) either b or c depending on polarity

Ferroelectric materials are made to respond in a piezoelectric fashion by; a) using bi-metal electrodes b) using only D.C. voltage c) sintering the material d) poling the material

d) poling the material

A net dipole moment is found in ferroelectric ceramics such as PZT when; a) heated above the curie temperature b) the domains are frozen and aligned c) used under water d) use on highly retentive steel

b) the domains are frozen and aligned

In contact testing methods, the purpose of the layer of couplant is to; a) reduce attenuation b) stop back-scatter c) allow only compressional wave to enter the piece d) all of the above

a) reduce attenuation

Which of the following properties, when considering transducer materials, does quartz excel in? a) receiving constant b) transmitting constant c) dielectric constant d) coupling coefficient

a) receiving constant

Curie temperature of a transducer material will indicate; a) toxicity of vapour b) coupling constant c) acoustic impedance variations with temperature d) maximum work surface temperature

d) maximum work surface temperature

Internally reflected waves within a lightly loaded resonant transducer (ie. acoustic impedance on either side is lower than the transducer's); a) nullify resonance b) change the resonant frequency c) increase the maximum oscillation amplitude d) are totally internally refracted

c) increase the maximum oscillation amplitude

For continuous wave testing, rise time of the transducer oscillation relative to the applied driving voltage is; a) longer than fall time b) shorter c) about the same d) not important

d) not important

The first oscillation of a piezoelectric element hit by an alternating voltage pulse is; a) higher than all other oscillations in that pulse b) lower than all other oscillations in that pulse c) never higher than the second oscillation in that pulse d) higher or lower than the second oscillation depending on the front loading

c) never higher than the second oscillation in that pulse

Acoustic transformers are constructed of; a) araldite b) cork c) tungsten loaded epoxies d) any transitional layer designed to achieve maximum power transfer

d) any transitional layer designed to achieve maximum power transfer

The purpose of tungsten powder incorporated in transducer backings is to; a) increase acoustic impedance b) increase absorption of backward moving ultrasound c) both a and b d) none of the above

c) both a and b

Nickel and its compounds as well as cobalt and ferrites differ from other magnetostrictive materials in that they; a) expand in applied magnetic fields b) shrink in applied magnetic fields c) are anti-magnetostrictive d) are also piezoelectric

b) shrink in applied magnetic fields

Magnetostrictive transducers have application in; a) drilling b) welding c) ultrasonic cleaning d) all of the above

d) all of the above

In a standing wave, the points of zero pressure change are called; a) null points b) nodes c) anti-nodes d) the still zone

b) nodes

A lens shape that would result in a divergent beam in optics gives a convergent beam in ultrasonic's because; a) electromagnetic wavelengths are shorter b) electromagnetic waves are faster in solids than liquids c) mechanical waves are usually faster in solids than liquids d) none of the above

c) mechanical waves are usually faster in solids than liquids

Ultrasonic transducers used in ultrasonic cleaning apparatus are operating at a frequency of approximately; a) 25 kHz b) 200 kHz c) 0.5 MHz d) 50 MHz

a) 25 kHz

EMC The purpose of ultrasonic vibrations added to the tip of a soldering gun when soldering aluminum or magnesium is to; a) eliminate the need for penetrant inspection b) make a fine grain structure with high shear strength c) break through the oxide coating d) all of the above

c) break through the oxide coating

Which of the following is not a therapeutic application of medical ultrasound; a) ultrasonic treatment of arthritis, bursitis, sciatica b) destruction of brain tissue in neuro-sonic surgery c) establishing health, sex and age of a fetus d) destruction of gall stones

c) establishing health, sex and age of a fetus

The timebase or baseline is displayed on a CRT as a horizontal line by means of; a) line focus electronics b) line focus optical lenses c) a light spot moving across phosphor d) none of the above

c) a light spot moving across phosphor

Increasing the pulse repetition frequency will result in; a) decreasing sensitivity b) increased resolution c) altering the probes' frequency output d) brightening the baseline

d) brightening the baseline

If it is difficult to resolve two defects separated by 0.5 cm, resolution may be improved by; a) increasing gain b) increasing sound path c) decreasing pulse length d) decreasing probe frequency

c) decreasing pulse length

Damping is achieved in an ultrasonic transducer by; a) electrical adjustment of the pulse b) using high loss backing c) using matching layers between crystal and workpiece d) all of the above

d) all of the above

Elastic constants such as Young's modulus and the bulk modulus can be calculated from ultrasonic measurement of; a) attenuation b) reflection coefficients c) acoustic velocities d) frequency domains

c) acoustic velocities

In order to accurately determine acoustic velocities you must know; a) your instruments PRF b) Snell's law c) Young's modulus or the bulk modulus d) the thickness of the test piece

b) Snell's law

Measurement of changes in sound velocity are used for determining; a) density b) flow rates of fluids c) thickness d) all of the above

b) flow rates of fluids

Linearity of an ultrasonic machine's timebase must be within; a) 1mm b) 2mm c) 1% d) 10%

c) 1%

Which item is not always marked on all standard transducers sold for NDT purposes; a) frequency b) exit point c) crystal dimensions d) serial number

b) exit point

In UT, signal-to-noise ratio is a function of; a) the probe b) the oscilloscope c) a combination of probe and scope d) none of the above

c) a combination of probe and scope

When evaluating the performance of a probe-instrument combination, far field resolution is limited by; a) the probes' functional frequency b) instrument gain c) available suppression d) the test surface of the calibration block

a) the probes' functional frequency

The arbitrary amplitude response from flat bottomed or side drilled holes is used to establish sensitivity level because; a) sensitivity is optimized b) resolution is optimized c) results can be reproducible d) both a and b

c) results can be reproducible

Viscosity of couplant chosen for a contact ultrasonic inspection will usually depend on; a) probe size b) nominal frequency c) surface condition d) sensitivity required

c) surface condition

In longitudinal wave inspection of the parent metal adjacent to a weld, minimum sensitivity is usually set such that; a) it is 6 dB over the 80% FSH level for the appropriate side drilled hole b) it is 20 dB over the 80% FSH level for the appropriate side drilled hole c) backwall echo is 100% FSH in the absence of defects d) none of the above

c) backwall echo is 100% FSH in the absence of defects

When doing an ultrasonic weld inspection, material thickness, weld preparation configuration, defect type and orientation are the main considerations for; a) probe dimensions b) frequency c) probe angle d) all of the above

c) probe angle

Gain corrections to compensate for attenuation are dependent on; a) frequency used b) grain structure of test material c) pulse energy d) a and b

d) a and b

The IIW Block #1 is used to calibrate; a) range b) exit point c) refracted angle d) all of the above

d) all of the above

When calibrating an ultrasonic instrument for range, the maximum distance of interest should not be less than; a) 100 mm b) 200 mm c) one half the horizontal scale d) two thirds the horizontal scale

d) two thirds the horizontal scale

DGS diagrams are used to establish; a) defect depth b) defect size c) correct probe dimensions d) beam divergence

b) defect size

CHECK re 'diagram' In the DGS (AVG German) system of defect sizing, the diagram relates to sound path distance to the _________ to obtain the relative distance. a) probe size b) near-field length c) stand-off distance d) depth of defect

b) near-field length

Where geometry permits in weld inspection, the distance you need to move the probe back from the weld to ensure 100% volume inspection is; a) 1/2 skip from the weld centre-line b) 1 full skip from the weld centre-line c) 1/2 skip from the edge of the heat affected zone d) 1 full skip from the HAZ edge

d) 1 full skip from the HAZ edge

During manual scanning, detection of obliquely oriented defects is improved by; a) using a lower frequency b) longitudinal wave inspections c) adding swivel motion to the angle beam probe d) all of the above

c) adding swivel motion to the angle beam probe

Shear-wave probe angle for contact testing of plate between 10mm and 100 mm thick is; a) 45 and 60 degrees b) determined by probe frequency chosen c) dependent on plate thickness, position and nature of defect d) none of the above

c) dependent on plate thickness, position and nature of defect

Given a flat plate 25mm thick, the full skip range distance with a 60 degree probe is; a) 35mm b) 50mm c) 87mm d) not possible to determine

c) 87mm

The half skip range on a 16mm thick plate with a 70% probe is; a) 24mm b) 35mm c) 44mm d) 67mm

c) 44mm

A defects' vertical extent is deduced by __________ motion of the probe; a) lateral b) traversing c) rotational d) orbital

b) traversing

A sharp signal with large amplitude response seen from one side of a weld but not the other, having a sharp drop off with both rotational and orbital motion would indicate the presence of; a) porosity b) lack of fusion c) slag d) cracking

b) lack of fusion

The use of ultrasonic methods to check fillet welds is usually restricted to determining the extent of penetration. This is best facilitated by; a) a guidance system to hold the probe at a fixed distance b) c-scan presentations c) 45 and 60 degree probes in tandem d) holographic techniques

a) a guidance system to hold the probe at a fixed distance

Size estimations of defects based on amplitude response are; a) the best option available b) never reliable c) used by all codes d) always referenced to side drilled holes or notches

b) never reliable

The amplitude reference line used to compare flaw response to reference hole response at varying depths is abbreviated; a) ARL b) AVG c) DAC d) DGS

c) DAC

If you are drawing a DAC for an inspection range of 200mm and your response from the 3/8 node reference hole at 125mm has already dropped to 10% FSH you will have to use; a) a new calibration block b) larger reference holes c) the DGS (AVG) system d) a split DAC

d) a split DAC

A transfer value is established using; a) published attenuation values for the alloy tested b) two shear wave probes in a through transmission technique c) DGS (AVG) curves d) multiple back-echoes from a normal beam probe

b) two shear wave probes in a through transmission technique

If coupling conditions on a test piece are better than on a calibration block the transfer value will be; a) greater than zero b) less than zero c) not used d) 1 (one)

b) less than zero

Vertical extent of a defect is determined using; a) a 6 dB drop method b) a 10 dB drop method c) a 20 dB drop method d) any of the above is acceptable if the appropriate beam spread plot is made for comparison

d) any of the above is acceptable if the appropriate beam spread plot is made for comparison

Acceptability of a defect is determined by; a) code or customer requirements b) amplitude relative to reference c) length d) type of flaw

a) code or customer requirements

The most pronounced effects of beam deviation by surface roughness are had when using; a) immersion testing b) low frequency transducers c) 70 degree contact probes d) normal beam probes

c) 70 degree contact probes

The result of increasing the temperature of a test piece from 10^oC to 30^oC is; a) increase sensitivity b) decrease the refracted angle c) decrease the acoustic velocity d) all of the above

d) all of the above

The ability to discern individual defects separate from the initial interface signal is called; a) dead zone limit b) near surface resolution c) surface acuity d) damping

b) near surface resolution

The IIW Block #1 cannot be used to calibrate; a) angle beam resolution b) range for time-base c) time-base linearity d) sensitivity

a) angle beam resolution

The maximum amplitude response from the 1.5mm diameter hole in the IIW Block #1 is used to determine; a) longitudinal wave sensitivity b) shear wave sensitivity c) dead zone distance d) both a and b

d) both a and b

IIW blocks are constructed of; a) ASTM-A36 steel b) stainless steel c) aluminum d) any metal or alloy

d) any metal or alloy

CHECK The 91mm step in the IIW Block #1 is used for; a) setting shear wave range with longitudinal waves b) establishing non-standard ranges c) shear wave resolution determinations d) none of the above

a) setting shear wave range with longitudinal waves

The purpose of the small Rompas or DIN block (IIW Block #2) is; a) range calibration b) determining exit point of probe c) determining actual refracted angle d) all of the above

d) all of the above

The 5mm diameter through hole in the DIN or ROMPAS block is used for checking; a) shear wave sensitivity b) longitudinal wave sensitivity c) beam angle d) all of the above

d) all of the above

When setting sensitivity of a longitudinal probe using the IIW blocks; a) total number and size of last echo are used b) response from the side drilled hole is used c) both a and b can be used d) IIW blocks are never used to set sensitivity

c) both a and b can be used

The dB difference between a signal 25% FSH and 100% FSH is; a) 6 dB b) 8 dB c) 10 dB d) 12 dB

d) 12 dB

To reduce the influence of incident angle when evaluating beam characteristics, the preferred target is; a) a cylindrical target at right angles to beam axis b) a spherical target of tungsten c) a flat bottom hole d) vee notches

a) a cylindrical target at right angles to beam axis

Given that maximum acoustic intensity occurs at the focal point, the focal point for a flat 100mm diameter 4 MHz probe in water is; a) 10mm inside the probe damping b) the probe face c) the end of the near zone d) none of the above

c) the end of the near zone

In the AVG (DGS) diagrams, originated by Krautkramer in 1959, the reduced range is given; a) as a fraction of the near zone b) in millimeters only c) as a ratio of the probe diameter d) where the amplitude equals the ideal backwall echo

a) as a fraction of the near zone

In immersion testing, defect sizing is improved in the flaw traverse technique measuring probe movement to 6 or 20 dB drop levels by use of; a) lower frequency probes b) focused probes c) Y-cut transducer elements d) oil coupling instead of water

b) focused probes

To determine the functional, or operating frequency of a probe, you need; a) a UT machine capable of R.F. display b) a frequency analyzer c) to know the probe diameter and its near zone as measured in water d) any of the above can be used

d) any of the above can be used

The resolving power of an ultrasonic system depends primarily on the; a) loop gain of the transducer b) operating frequency c) amount of gain used in the receiver amplifier d) pulse energy

b) operating frequency

When a flaw has a size that is less than the wavelength of ultrasound impinging on it,: a) the AVG (DGS) system must be used for sizing. b) dimensions are determined using the 20 dB drop method. c) it is not possible to determine the flaws' shape. d) it cannot be detected.

c) it is not possible to determine the flaws' shape.

Signal averaging, correlation, and filtering are techniques used in ultrasonic systems to; a) extract weak signals from incoherent noise b) improve resolution c) characterize defects for type d) none of these techniques are used in ultrasonic testing

a) extract weak signals from incoherent noise

The process where by a re-current signal is extracted from incoherent noise is called; a) amplitude modulation b) frequency modulation c) signal averaging d) filtering

c) signal averaging

Receiver noise must often be filtered out of a test system. Receiver amplifier noise increases proportionally to; a) the square root of the bandwidth b) the inverse square of the bandwidth c) attenuation d) temperature

a) the square root of the bandwidth

A group of ultrasonic transducers arranged in some form of geometric pattern with individual transducers use sequentially as transmitters, receivers or both is called a; a) sequenced array b) switched pulser c) C-scan array d) multi-element probe

a) sequenced array

Which is not used as an acoustic imaging method? a) deconvolution b) sequenced array c) liquid-surface levitation d) holography

a) deconvolution

In order to determine a particular material parameter using UT, you would need to find its,: a) critical angle. b) acoustic velocity and acoustic impedance. c) attenuation. d) any or all of the above depending on the parameter sought.

d) any or all of the above depending on the parameter sought.

The so called delta technique derives its name from; a) its origins in the Mississippi delta b) measurements of changes in velocity (delta "V") c) the triangular juxtaposition of transmitter, receiver and flaw d) none of the above

c) the triangular juxtaposition of transmitter, receiver and flaw

Increasing a focused probe's focal length can have the advantage of increasing focal depth, but this is achieved at the expense of; a) increasing attenuation b) increasing focal spot size c) reducing resolution d) both b and c

d) both b and c

Which is not an advantage of electromagnetic acoustic transducers (EMAT)? a) high electric to acoustic power conversion b) can inspect rough or coated surfaces c) non-contacting d) inspection of high temperature surfaces

a) high electric to acoustic power conversion

In highly automated inspection apparatuses, ultrasonic phased arrays permit the; a) elimination of mechanical scanning apparatus. b) increased resolution over a greater depth range. c) control of beam shape. d) all of the above.

d) all of the above.

Rayleigh waves have: a) distinctly different velocities from longitudinal and shear waves in the same medium b) ellipsoidal particle displacement c) a velocity slightly less than shear waves in the same medium d) all of the above

d) all of the above

For crystalline material to have piezoelectric properties it must have; a) asymmetry of crystal axes b) silicon as one of its component elements c) nuclear spin parity d) no unstable isotopes

a) asymmetry of crystal axes

For unpoled poly-crystalline piezoelectric materials, an applied pressure results in; a) polar alignment of crystal b) radial mode vibration c) maximum voltage d) zero net voltage

d) zero net voltage

Even under ideal conditions, the electro mechanical coupling coefficient (k) will not exceed; a) 0.1 b) 1.0 c) 10 d) 100

b) 1.0

If the product of the relative transmitter and receiver efficiencies of quartz is 1, which of the following piezomaterials would have a product less than 1? a) PZT b) ZnO c) PVDF d) none of the above

d) none of the above

A dual crystal probe using PZT as a transmitter and PVDF as a receiver, as compared to just PZT used in the send-receive mode would be; a) about 7 times more efficient b) half as efficient c) hampered by low signal to noise ratio d) useless

a) about 7 times more efficient

The purpose of using metal powder in epoxies as probe backing material is to; a) increase acoustic impedance of the backing to match the ceramic piezoelements' acoustic impedance b) provide an electric conductor to the back electrode c) decrease bandwidth d) none of the above

a) increase acoustic impedance of the backing to match the ceramic piezoelements' acoustic impedance

In ultrasonic testing, beam focusing is accomplished by; a) placing lenses in front of the planar transmitter b) suitably curved piezo material c) specimen geometry d) all of the above

d) all of the above

The result of a cylindrical shaped lens on the front of an ultrasonic probe is a(n); a) point focused beam b) line focused beam c) asymptotic beam d) negatively focused beam

b) line focused beam

Which is not an advantage of electromagnetic acoustic transducers (EMATs)? a) no couplant needed b) hot surfaces are more easily inspected c) easily shaped beams d) increased sensitivity over ferro electric probes

d) increased sensitivity over ferro electric probes

Electromagnetic acoustic transducers (EMATs) generate ultrasound by means of; a) cosmic awareness b) eddy currents c) mechanical contact d) magnetic deformations

b) eddy currents

EMATs cannot be used to generate ultrasound in; a) non-conductive material b) magnetic metals c) non-magnetic metals d) both a and b

a) non-conductive material

The most common method used to determine the nature of a probes' sound field is by: a) fast fourier transforms. b) impedance curves. c) side drilled holes. d) using two transducers, one transmitting and the other receiving.

c) side drilled holes.

An angle beam probe is checked for refracted angle on an IIW and is found to be an angle of 44 degrees; the IIW blocks' temperature is 10^oC. If the test piece is 40^oC, will the refracted angle will be; a) more b) less c) the same d) not possible to know

a) more

To determine the dominant frequency of a probe you would require; a) an unrectified signal on a baseline calibrated in time b) a rectified signal on a baseline calibrated in distance c) a reference probe d) an impedance matching circuit

a) an unrectified signal on a baseline calibrated in time

The time interval in microseconds between the first and last instant at which the value of the pulse reaches 10% of its peak amplitude is considered the; a) pulse length b) 20 dB drop length c) dead zone d) rise time

a) pulse length

When determining signal-to-noise ratio the suppression control is set at; a) maximum b) minimum c) 50% d) suppression setting is not important

b) minimum

When determining signal-to-noise ratio, the noise is attributable to; a) electrical noise from machine, cable and probe b) metal grain structure c) both a and b d) inability to focus the baseline

c) both a and b

Probe index refers to; a) nominal frequency of the probe b) beam exit point c) the refracted angle in the test piece d) the incident angle from perspex

b) beam exit point

For a given range, for deviations of +/-2^o in refracted angles, which will result in the greatest depth error? a) 70^o probes b) 60^o probes c) 45^o probes d) error will be constant at all angles

a) 70^o probes

Depth of the dead zone is determined by; a) probe design b) pulse energy setting c) gain setting d) all of the above

d) all of the above

A discontinuity whose shape, size location or properties make it detrimental to the useful service of the product in which it occurs or which exceeds the accept/reject criteria is a(n); a) defect b) slag inclusion c) crack d) anomaly

a) defect

A response or evidence of a response in NDT that requires interpretation is called; a) an indication b) a defect c) a flaw d) signal-to-noise ratio

a) an indication

The component of ultrasonic wave attenuation resulting from conversion of mechanical energy to heat is called; a) acoustic absorption b) coupling c) divergence d) acoustic impedance

a) acoustic absorption

The property which determines acoustic transmission across a boundary between two media is termed; a) acoustic impedance b) electric impedance c) conductivity d) transmissivity

a) acoustic impedance

Coupling two media to provide optimum transfer of ultrasonic energy between them is; a) a code requirement b) acoustic impedance matching c) best accomplished by dry coupling d) all of the above

b) acoustic impedance matching

For a given ultrasonic beam impinging on a surface, the angle of incidence, the angle of reflection and the normal to that surface are; a) always equal b) never equal c) found by the inverse squared law d) in the same plane

d) in the same plane

Loss of acoustic energy in a material due to scatter, absorption and dispersion is called; a) suppression b) attenuation c) damping d) all of the above

b) attenuation

A curve showing the relationship of amplitude to distance travelled to reflectors of the same area is usually referred to as a(n); a) AVG curve b) DAC curve c) DGS curve d) NDT curve

b) DAC curve

The ultrasonic pulse received from the boundary of a body normal to the beam axis is termed; a) backwall echo b) a multiple reflection c) the normal echo d) a defect

a) backwall echo

An ultrasonic display in rectangular coordinates where distance or time of flight is represented in one direction and probe displacement represented on the other and reflected pulses as bright marks on a dark background (or vise versa) is called a(n); a) A-scan b) B-scan c) C-scan d) tomograph

b) B-scan

Noise generated by the transmitting transducer which is produced in the receiving transducer of a dual crystal probe is called; a) signal from noise effect b) cross-talk c) acoustic pick-up d) FM cross-over

b) cross-talk

An assembly of ultrasonic crystals mounted so as to behave as though it were a single crystal is called a(n); a) acoustic mat b) crystal mosaic c) phased array d) linear array

b) crystal mosaic

The time interval between the initial pulse and the initiation of the time base sweep is termed; a) range b) time of flight c) programmed off-set d) delay

d) delay

The frequency at which the overall response of an ultrasonic pulse-echo flaw detection system is maximum, is the; a) dominant frequency b) resonance frequency c) nominal frequency d) anti-resonance frequency

a) dominant frequency

The lowest acoustic frequency which will cause a condition of resonance to be established in a given material of given thickness is the _________ frequency. a) fundamental b) parallel c) series d) anti-resonance

a) fundamental

A probe which incorporates separate transmit and receive crystals in the same housing is called a; a) dual crystal probe b) T-R probe c) delta probe d) normal probe

a) dual crystal probe

The unit of sound (or electrical) gain or attenuation, dB is; a) one tenth of a bell b) a ratio of voltages or intensities c) derived from naval protocol d) both a and b

d) both a and b

The display of remnant reflections originating from previously transmitted pulses due to too high a PRF are called; a) transients b) trip signals c) ghost echoes d) none of the above

c) ghost echoes

Harmonic frequencies occur at; a) 2 times the fundamental frequency b) 3 times the fundamental frequency c) 4 times the fundamental frequency d) all of the above

d) all of the above

The boundary between any two media, of different acoustic impedance values, is termed a(n); a) interface b) divide c) interlude d) front

a) interface

A wave that is propagated in thin material, and whose velocity is dependent on frequency and material thickness, is called a; a) Lamb wave b) Rayleigh wave c) shear wave d) new wave

a) Lamb wave

The repeated reflections of ultrasonic pulses from between surfaces or discontinuities within a body are called; a) ghost echoes b) sing-around c) multiple echoes d) wrap-around

c) multiple echoes

A normal probe is one which; a) operates at half wave resonance b) operates at quarter wave resonance c) has tungsten powder imbedded in its backing epoxy d) introduces sound into a test piece at right angles to the surface

d) introduces sound into a test piece at right angles to the surface

The method whereby a discontinuity is detected and evaluated using reflected pulses, is named; a) pulse-echo method b) through transmission c) bulk wave testing d) crack tip diffraction

a) pulse-echo method

The number of times per second that an ultrasonic transducer is excited to produce a pulse is; a) determined by the crystal thickness b) a function of the cable capacitance c) the pulse repetition frequency d) all of the above

c) the pulse repetition frequency

The gain or attenuation setting at which indications are assessed is the ________ level. a) reference b) scan c) threshold d) bell

a) reference

Instrument settings which relate a reference echo of reproducible amplitude with which other instrument settings relating to a discontinuity echo are compared is the; a) scanning level b) threshold level c) reference sensitivity d) overall system gain

c) reference sensitivity

Addition of suppression or reject to a display effectively; a) filters out unwanted noise b) reduces dynamic range c) increases sensitivity d) none of the above

b) reduces dynamic range

The relationship between amplitudes of an indication in A-scan presentation and the magnitude of the corresponding received signals is used to determine; a) vertical linearity b) manual scanning speed c) longitudinal/shear mode energy ratios d) none of the above

a) vertical linearity

The device which incorporates one or more ultrasonic crystals mounted inside a liquid filled flexible tire is commonly called a; a) rubber tester b) rotating head probe c) wheel probe d) plate probe

c) wheel probe

Which pulse method of ultrasonic testing uses only a single crystal? a) pulse-echo b) pitch-catch c) through-transmission d) all of the above

a) pulse-echo

The source of ultrasound in acoustic emission techniques is; a) sudden relaxation of stresses within the material b) a transmitter crystal c) rotary wire brushes d) static discharge

a) sudden relaxation of stresses within the material

Resolving power of broadband transducers; a) increases with sound path distance b) decreases with sound path distance c) is independent of sound path distance d) depends solely on near field length

b) decreases with sound path distance

Examination of a metal's elastic properties by increasing the angle of incidence until either the longitudinal or shear mode disappears is called; a) wave mode analysis b) spectral analysis c) specular analysis d) critical-angle analysis

d) critical-angle analysis

When doing immersion critical-angle analysis, the pitch-catch technique is used. The receiver probe, is used to study the; a) reflected longitudinal wave b) reflected transverse wave c) transmitted longitudinal wave d) Rayleigh waves

a) reflected longitudinal wave

SKIP UNTIL CHECKED FOR CORRECTNESS Non-contact ultrasonic coupling, ie. coupling across an air gap has its advantage in; a) avoiding fluid contamination of test piece b) testing at elevated temperatures is possible c) avoiding transducer wear on rough surfaces d) all of the above

d) all of the above

When performing a normal beam inspection of 60mm thick plate by immersion technique, the minimum water path to avoid water path multiples in the first metal wall thickness display is; a) 15mm b) 30mm c) 60mm d) 240mm

a) 15mm

If the longitudinal waves are required at an angle other than zero degrees from the normal in the test piece; a) the incident angle must be less than the first critical angle b) the incident angle must be less than the second critical angle c) the incident angle must be between the first and second critical angles d) you are out of luck-it can't be done

a) the incident angle must be less than the first critical angle

Although no longer commonly used for thickness testing of steel plate, resonance testing still finds application in; a) flaw detection in integrated circuits b) locating non-bonded areas in rubber to metal c) shadow technique ultrasonic testing d) all of the above

b) locating non-bonded areas in rubber to metal

Ultrasonic systems similar to those used in NDT are used in; a) ultrasonic welding. b) diagnostic medicine. c) de-watering units. d) ultrasonic machining.

b) diagnostic medicine.

Transducers used for resonance measurements would more likely be; a) broadband-type pulse b) high-Q factor c) low-Q factor d) none of the above

b) high-Q factor

When information is presented as a B-scan on an oscilloscope, intensity (or amplitude) of a signal is indicated by; a) strobe effects for signals over a threshold amplitude b) digital readout on the corner of the screen c) brightness of the spot on the scope d) none of the above

c) brightness of the spot on the scope

When measuring crack depth using shear-wave sound paths, amplitude drop and probe travel, you need in addition to various distances and the refracted angles; a) a transmitting and a receiving transducer b) the beam width in the vertical plane c) maximum amplitude with respect to a side drilled hole d) maximum amplitude with respect to a flat bottom hole

b) the beam width in the vertical plane

For a given flaw, with a physical vertical extent of 11mm, the probe requiring the maximum forward travel to locate the flaw ends would be the; a) 0^o b) 45^o c) 60^o d) 70^o

d) 70^o

An increase in attenuation or a decrease in velocity in a material is generally indicative of; a) degradation or loss of strength b) an increase in compressive loading c) an increase in tensile strength d) decreasing pulse frequency

a) degradation or loss of strength

Attenuation studies in ultrasound could be used to determine; a) average gain size of metals b) yield point of materials during elastic-plastic deformation c) fracture toughness of stainless steel d) all of the above

d) all of the above

Ultrasonic methods used to monitor or detect fatigue cracks are based on; a) attenuation effects b) amplitude of reflection energy c) both a and b d) none of the above

c) both a and b

An advantage of using ultrasonic surface waves over other wave modes is; a) good sensitivity to subsurface defects b) the ease of focusing the beam c) test piece contours are followed without loss due to direction changes d) none of the above

c) test piece contours are followed without loss due to direction changes

The weld defect that results when a weld puddle solidifies from the outer edges and causes stresses sufficient to produce cracking is; a) crater cracking b) underbead cracking c) transverse cracking d) puddle jumping

a) crater cracking

The purpose of removing a weld cap by grinding it flush with the base metal in preparation for ultrasonic testing is to; a) reduce scatter from redirection of beam b) improve volumetric coverage c) increase sensitivity to near surface defects d) all of the above

d) all of the above

When testing tubular products with ultrasonics it is essential to ensure a fixed alignment between the probe and workpiece since a slight shift of tube axis could result in; a) a large change in incidence angle b) damaging the probe c) differential losses in frequency content d) none of the above

a) a large change in incidence angle

In immersion ultrasonic testing of tubular products, line focused probes have an advantage over point focused probes in that; a) higher frequencies are available b) higher inspection rates are possible c) higher resolution is achieved d) higher sensitivity is achieved

b) higher inspection rates are possible

When inspecting tubing using ultrasonic immersion methods in the tube mill; a) the tube is rotated under the ultrasonic probes b) the probes are rotated around the tube c) both a or b can be arranged d) none of the above

c) both a or b can be arranged

Lamb waves are used to inspect; a) threaded bar stock b) for inclusions in TIG welded root passes c) thin plate d) all of the above

c) thin plate

In general, ultrasonic testing of cast iron is; a) done at frequencies from 1-2 MHz b) by immersion methods only c) both a and b d) avoided

d) avoided

Which of the following non-metals would more commonly be tested by ultrasonics in the kilohertz range of frequencies? a) wood b) concrete c) rubber d) all of the above

d) all of the above

Ultrasonics when used on timber (ie. logs) can determine; a) age by counting rings b) diameter c) presence or absence of decay d) none of the above, ultrasound is not used to test timber

c) presence or absence of decay

Ultrasonic velocities of glasses such as quartz, fused silica and pyrex are; a) not possible to determine b) available for only the longitudinal mode c) about the same as steel d) about the same as water

c) about the same as steel

Ultrasonics has been successfully used in testing rubber tires for determining; a) porosity location b) de-lamination location c) the state of cure d) all of the above

d) all of the above

Ultrasonic holography has an advantage over other imaging techniques in that it provides; a) total information from a single pulse b) a 3-dimensional display of defects c) maximum inspection speed d) the best sensitivity of all imaging systems

b) a 3-dimensional display of defects

Non-destructive testing is one of many applications of low-intensity ultrasound. Which of the following is not an example of low-intensity ultrasound application. a) acoustic holography b) ultrasonic fish-finders c) ultrasonic cleaning d) ultrasonic flowmeters

c) ultrasonic cleaning

The weak emission of light that sometimes accompanies cavitation in high intensity ultrasonic fields is called; a) sonoluminescence b) fluorescence c) bioluminescence d) ultraluminescence

a) sonoluminescence

Diagnostic medical application of low intensity ultrasound has its advantage in; a) its ability to detect phenomena X-rays cannot b) destroying gall stones c) generating therapeutic heat d) all of the above

a) its ability to detect phenomena X-rays cannot

The Doppler effect is utilized in ultrasonic; a) flaw detection b) flow meters c) B-scanners d) cleaners

b) flow meters

Ultrasound intensity used in low intensity diagnostic testing (such as nondestructive testing) is on the order of a) 100ÊW/cm˝ b) 100mW/cm˝ c) 100kW/cm˝ d) 100MW/cm˝

b) 100mW/cm˝

DELETE Steel ball bearings would probably be tested non-destructively using; a) ultrasonics b) liquid penetrant c) magnetic particles d) radiography

b) liquid penetrant

DELETE The term defect or flaw indicates; a) a minimum or maximum size b) suitability of a part for a given purpose c) nature of the fault d) none of the above

d) none of the above

Ultimately the cause of any crack is; a) corrosion b) re-crystallization c) stress d) strain

c) stress

EMC Localized heating of metal objects can result in; a) "crazy" cracks b) grinding cracks c) arc strike cracks d) all of the above

d) all of the above

EMC In a valve casting, sponginess; a) could result in a leak b) could be found using liquid penetrant c) is easiest found using ultrasonics d) both a and b

d) both a and b

The term pipe refers to; a) a forging defect b) a weld defect c) central shrinkage in an ingot d) a central blowhole in a casting

c) central shrinkage in an ingot

DELETE A surface breaking crack located by ultrasonics; a) will be easily located using eddy currents b) may not by located by another NDT method c) will be shorter if located with LPI d) will be longer if located with LPI

b) may not by located by another NDT method

If a procedure fails to take into consideration a significant variable, such as temperature, the result will be; a) unreliable b) missed defects c) lack of repeatability d) over sensitivity

a) unreliable

If it is possible to automate a previously manually performed scan, you can always expect; a) faster inspections b) more accurate results c) improved flaw detection reliability d) all of the above

c) improved flaw detection reliability

When dealing with ultrasonic nondestructive testing the letters PZT stand for; a) Paul Zamphir Tait, the discoverer of the piezo-ceramics b) lead zirconate titanate c) phosphoric zirconate tungstenate d) none of the above

b) lead zirconate titanate

The most commonly used backing used in ultrasonic transducers used in NDT is; a) air b) spur's epoxy c) epoxy resin filled with tungsten powder d) brass

c) epoxy resin filled with tungsten powder

The material added to epoxy resin to increase acoustic impedance of the probe backing is usually; a) Rochelle salt b) iron filings c) tungsten powder d) PbO (lead oxide)

c) tungsten powder

The backward moving energy in an ultrasonic probe is damped by; a) natural attenuation of air b) defocusing lenses c) scattering by tungsten particles d) none of the above

c) scattering by tungsten particles

The least difficult aspect of a defect to determine using ultrasonics is; a) length b) height c) elastic constants d) yield stress reduction on the component

a) length

In time of flight diffraction techniques, the first wave to arrive at the receiving probe is the _________ wave. a) Rayleigh b) diffracted c) lateral d) reflected

c) lateral

The longitudinal blurring of ultrasonic B-scan images that results due to ultrasonic beam width can be reduced by; a) using a lower frequency probe b) synthetic aperture focusing technique (saft) c) increasing the soundpath d) using immersion methods.

b) synthetic aperture focusing technique (saft)

In Snell's Law, there will be no first critical angle if the; a) incident angle does not exceed 89 degrees b) acoustic velocity in the refracting medium is less than in the incident medium c) acoustic impedance of the refracting medium is greater than 1 d) none of the above, there will always be a first critical angle

b) acoustic velocity in the refracting medium is less than in the incident medium

The inverse sine of the ratio of the acoustic velocity in the incident medium to refracting medium's acoustic velocity gives; a) the first critical angle b) the second critical angle c) the third critical angle d) the critical angle, which critical angle depends on the mode velocity used

d) the critical angle, which critical angle depends on the mode velocity used

The inverse sine of the ratio of the _____ velocities gives the first critical angle. a) refracted long and incident shear b) incident long and refracted long c) incident long and refracted shear d) incident long and reflected long

b) incident long and refracted long

EMC In the welding process, removal of weld metal and base metal from the opposite side of a welded joint to ensure complete penetration upon welding from that side is called; a) de-welding b) beveling c) back gouging d) joint preparation

c) back gouging

In the welding process, removal of weld metal and base metal from the opposite side of a welded joint to ensure complete penetration upon welding from that side is called; a) de-welding b) beveling c) back gouging d) joint preparation

c) back gouging

EMC The preferred welding term for a blowhole is; a) tunneling b) gusher c) porosity d) gas pocket

c) porosity

The purpose of backing material at the root of a weld is; a) to support molten weld metal b) a heat sink c) to prevent lack of fusion d) all of the above

a) to support molten weld metal

EMC In welding processes, a preplaced filler metal which is fused into the root of a joint and thereby becomes part of the weld is a; a) chill b) chaplet c) consumable insert d) covered electrode

c) consumable insert

EMC A crack occurring in the depression at the termination of a weld bead is called a; a) hot tear b) termination crack c) heat check crack d) crater crack

d) crater crack

In a welded joint, the minimum distance from the root to the weld face is the; a) hypotenuse b) leg c) effective throat d) length of weld

c) effective throat

EMC The purpose of flux material in welding is; a) to stabilize the welding arc b) to protect the molten weld from atmosphere c) both a and b d) none of the above

c) both a and b

In welding, the area of base metal melted as determined on a cross-section of the weld is the; a) heat affected zone b) fusion zone c) dead zone d) twilight zone

b) fusion zone

The portion of base metal that has not been melted but whose mechanical properties or microstructure have been altered by heat of welding or cutting is called the; a) fusion zone b) heat affected zone c) dead zone d) twilight zone

b) heat affected zone

In a welding process using inert gas as a part of the operation, the purpose of the inert gas is to; a) react with the filler metal b) provide a protective atmosphere over the weld puddle c) increase the heat at the arc d) harden the weld metal deposited

b) provide a protective atmosphere over the weld puddle

EMC The protrusion of weld metal beyond the toe, face or root of a weld is called; a) overlap b) undercut c) pass d) bead

a) overlap

EMC Another term for the welding phenomenon called "suck-back" is; a) undercut b) blow-through c) concave root d) overlap

c) concave root

CHECK Cracking occurring in the heat affected zone that does not usually extend to the surface of the metal is; a) transverse cracking b) underbead cracking c) laminal cracking d) post weld heat treatment cracking

b) underbead cracking

In TIG welding the electrode manipulated by the welder is; a) made of tungsten b) not consumed c) both a and b d) none of the above

c) both a and b

When inspecting a curved surface with a contact probe it is advised to use; a) circular probes b) rectangular probes c) large probes d) small probes

d) small probes

When inspecting rough surfaces, such as castings, coupling efficiency can be improved by; a) using larger dimension probes b) increasing receiver gain c) using lower frequency probes d) increasing damping

c) using lower frequency probes

For contact testing of thin steel plate (5mm) it is recommended to use shear waves at 80 degrees. A significant problem to contend with however is; a) a large fraction of energy is converted to surface waves b) interference from side lobes c) identifying defects d) locating the position of defects

a) a large fraction of energy is converted to surface waves

CHECK You are required to scan the full volume of an unground tee joint weld on 100mm thick plate. Scanning is to be done from one side of the weld prep plate using a 45 degree probe. What is the scan distance you must move from the tee plate surface to ensure 100% coverage of the weld having a leg of 30mm? a) 142mm b) 230mm c) 283mm d) 300mm

b) 230mm

You are to scan an unground 50mm thick butt weld from one side of the weld only. The plate is 20mm thick and full volumetric coverage of the weld plus 20mm heat affected zone is needed. Weld face is 20mm wide. What is the maximum scan distance from the weld centre-line for this coverage with a 60 degree probe? a) 40mm b) 68mm c) 98mm d) 120mm

c) 98mm

A sharp narrow signal whose amplitude remains constant when orbited and drops off quickly with probe rotation is probably; a) lack of fusion b) an isolated pore c) slag d) a transverse crack

b) an isolated pore

A ragged, cluster of individual spikes is located and determined to be a defect. Sound path varies, amplitudes vary with rotation and orbiting with the probe. But the defect does not drop off completely when orbited. It is most likely a; a) crack b) slag inclusion c) porosity cluster d) lack of fusion

c) porosity cluster

A sharp narrow defect signal is located during a standard A-scan of a weld. Rotation and orbit of the defect cause it to drop off quickly with lateral probe motion the signal remains constant in both amplitude and sound path. It is most likely a; a) slag inclusion b) crack c) lack of fusion d) pore

c) lack of fusion

CHECK Given a butt weld in a 55mm thick plate, ground flush, you locate a large sharp narrow reflector with a sound path of 154mm and exit point 128mm from the weld centre line using a 45¯ degree probe. If it has length of 20mm the flaw is likely; a) lack of penetration b) mis-match c) lack of fusion d) suck back

c) lack of fusion

The purpose of a straight-edge probe guide to limit traversing motion is to; a) facilitate defect evaluation as to type b) limit scanning to a specific depth c) determine vertical extent d) none of the above

b) limit scanning to a specific depth

When performing a manual pulse-echo contact scan to evaluate the root area of a weld, a helpful aid is a(n); a) level 1 technician b) straight edged probe guide c) electronic gate d) threshold alarm

b) straight edged probe guide

Given an immersion probe with a focal length of 50mm in water, about what depth in steel would this probe focus if positioned with normal incidence 40mm over a steel plate (using water couplant)? a) 2.5 mm b) 5.0 mm c) 10 mm d) 40 mm

a) 2.5 mm

The probe used in the 30-70-70 mode converted method uses; a) 3 separate elements mounted at different angles b) 2 separate elements mounted at different angles c) a single element mounted to induce a 70 degree refracted Longitudinal wave d) a single element mounted to induce a 70 degree refracted Shear wave

c) a single element mounted to induce a 70 degree refracted Longitudinal wave

CHECK The indirect shear wave in the 30-70-70 mode conversion method is formed off the; a) 70 degree Longitudinal wave b) creeping wave c) direct shear wave d) damping material on the front of the probe shoe

b) creeping wave

Which is a limitation of the 30-70-70 mode conversion method? a) It cannot be performed with conventional probes b) It requires special calibration blocks c) Parallel surfaces are needed for mode conversion d) All of the above

d) All of the above

UT 2 - Test Questions Flashcards

(349 cards)