Eugene Cawley
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NDE Technician Non Destructive Testing Quiz on ET Level II Practice Test , created by Eugene Cawley on 18/12/2018.

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Eugene Cawley
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ET Level II Practice Test

ET Level II Practice Test

Question 1 of 89

1

A method of minimizing the effect of indications caused by
gradual dimensional changes while retaining the indications
caused by discontinuities is too:

Select one of the following:

  • A. include a high-pass filter in the eddy current test
    equipment.

  • B. include a low-pass filter in the eddy current test
    equipment.

  • C. increase the band pass of the amplifier.

  • D. use the impedance method of testing.

Explanation

Question 2 of 89

1

Which of the following methods may be used to improve the signal-to-noise ratio of an eddy current test system?

Select one of the following:

  • A. Filtering or differentiation.

  • B. Phase discrimination.

  • C. Integration.

  • D. All of the above.

Explanation

Question 3 of 89

1

In order to decrease the effect on conductivity readings due to variations in test part thickness:

Select one of the following:

  • A. the test frequency should be increased.

  • B. the test frequency should be decreased.

  • C. the fill factor should be decreased.

  • D. there is no practical method for decreasing this effect.

Explanation

Question 4 of 89

1

When testing by the eddy current method, discontinuities will be most easily detected when the eddy currents are:

Select one of the following:

  • A. coplanar with the major plane of the discontinuity.

  • B. perpendicular to the major plane of the discontinuity.

  • C. parallel to the major plane of the discontinuity.

  • D. 90 degrees out of phase with the current in the coil.

Explanation

Question 5 of 89

1

A term used to describe the effect observed due to a change in the electromagnetic coupling between a test specimen and a probe coil when the distance of separation between them is varied is:

Select one of the following:

  • A. fill factor.

  • B. edge effect.

  • C. end effect.

  • D. lift-off.

Explanation

Question 6 of 89

1

A term used to define the phenomenon where, at very high frequencies, the eddy current flow is restricted to an extremely thin outer layer of the conductor is:

Select one of the following:

  • A. skin effect.

  • B. high-frequency filtration.

  • C. low-frequency filtration.

  • D. any one of the above.

Explanation

Question 7 of 89

1

The fill factor when a 1/2-inch diameter bar is inserted in a 1-inch diameter coil is:

Select one of the following:

  • A. 0.5 or (50%)

  • B. 0.75 or (75%)

  • C. 1.0 or (100%)

  • D. 0.25 or (25%)

Explanation

Question 8 of 89

1

The term used to define the difference between actual instrument output and expected output as defined by a straight line calibration curve is:

Select one of the following:

  • A. phase shift.

  • B. nonlinearity.

  • C. lift-off.

  • D. skin effect.

Explanation

Question 9 of 89

1

Which of the following could be used to suppress unwanted high-frequency harmonics?

Select one of the following:

  • A. Low-pass filter.

  • B. Oscillator.

  • C. Phase discriminator.

  • D. High-pass filter.

Explanation

Question 10 of 89

1

The impedance change of an eddy current test coil due to a change in test part characteristics can be most easily analyzed as a combined change in:

Select one of the following:

  • A. capacitive reactance and resistance.

  • B. harmonic frequencies and inductive reactance.

  • C. signal amplitude and phase.

  • D. retentivity and harmonic frequencies.

Explanation

Question 11 of 89

1

The inductive reactance of a test coil can be calculated using the formula:

Select one of the following:

  • A. XL = 2 π L

  • B. XL = 1/2 π L

  • C. XL = 2 π f L

  • D. XL = W 2 π f

Explanation

Question 12 of 89

1

When conducting an eddy current test, variations in the test material can be detected as variations in:

Select one of the following:

  • A. test speed.

  • B. impedance of a pickup coil.

  • C. none of the above.

  • D. all of the above.

Explanation

Question 13 of 89

1

A term used to define two or more coils electrically connected in opposition such that any electromagnetic condition which is not common to both a test specimen and a reference specimen will produce an unbalance in the system is:

Select one of the following:

  • A. differential.

  • B. absolute.

  • C. laminar.

  • D. flying probes.

Explanation

Question 14 of 89

1

Tubing is generally inspected using:

Select one of the following:

  • A. U-shaped coils.

  • B. internal coils.

  • C. encircling coils.

  • D. Either B or C depending on configuration.

Explanation

Question 15 of 89

1

When testing small parts in an eddy current encircling coil for permeability measurements, which of the following test parameters may be considered important?

Select one of the following:

  • A. Length of the test sample.

  • B. Thickness of the test sample.

  • C. Cross-sectional area of the test sample.

  • D. all of the above.

Explanation

Question 16 of 89

1

In a test coil consisting of both a primary and secondary winding, the voltage across the secondary is a function of:

Select one of the following:

  • A. test material permeability.

  • B. test frequency.

  • C. geometry of the test object.

  • D. all of the above.

Explanation

Question 17 of 89

1

Eddy current testing relies on the principle of:

Select one of the following:

  • A. magnetostriction.

  • B. electromagnetic induction.

  • C. piezoelectric energy conversion.

  • D. magnetomotive force.

Explanation

Question 18 of 89

1

When the H field strength around a material is increased and
then decreased to zero, the induction field B within the part
does not return to zero. The term to define this B value when H has returned to zero is:

Select one of the following:

  • A. coercive force.

  • B. residual magnetism.

  • C. saturation value.

  • D. hysteresis loss.

Explanation

Question 19 of 89

1

The term used to define the value of H field required to
decrease the remanence of a material to zero is:

Select one of the following:

  • A. coercive force.

  • B. magnetizing force.

  • C. back emf.

  • D. the overlap value.

Explanation

Question 20 of 89

1

The three major specimen parameters which influence eddy current testing are:

Select one of the following:

  • A. electrical conductivity, frequency, and material geometry.

  • B. density, permeability, and frequency.

  • C. electrical conductivity, permeability, and material geometry.

  • D. thermal conductivity, electrical conductivity, and permeability.

Explanation

Question 21 of 89

1

Doubling the number of turns on a coil will:

Select one of the following:

  • A. double the indicators.

  • B. halve the inductance.

  • C. decrease the inductance by a factor of four.

  • D. increase the inductance by a factor of four.

Explanation

Question 22 of 89

1

Frequency ratio, f/fg can be defined as:

Select one of the following:

  • A. the argument of the mathematical function describing the electromagnetic field within the test specimen.

  • B. test frequency divided by limit frequency.

  • C. neither of these.

  • D. both of these.

Explanation

Question 23 of 89

1

When testing tubing, using and encircling (OD) coil, what is the
phase relationship of the output signals from identical ID and OD
discontinuities?

Select one of the following:

  • A. The signals are in phase.

  • B. The phase of the OD discontinuity leads the phase of the ID
    discontinuity.

  • C. The phase of the OD discontinuity lags the phase of the ID
    discontinuity.

  • D. Indeterminate.

Explanation

Question 24 of 89

1

A term used to define an instrumentation technique which discriminates between variables in the test part by the different phase angle changes which these conditions produced in the test signal is:

Select one of the following:

  • A. phase distortion.

  • B. phase shifting.

  • C. phase discrimination.

  • D. phase analysis.

Explanation

Question 25 of 89

1

If the characteristic frequency (fg) of a material is 125 Hz, the test frequency required to give an f/fg ratio of 10 would be:

Select one of the following:

  • A. 1.25 Hz.

  • B. 12.5 Hz.

  • C. 1.25 kHz.

  • D. 12.5 kHz.

Explanation

Question 26 of 89

1

A term used to define any change in a sinusoidal signal when the output is not a linear reproduction of the input is:

Select one of the following:

  • A. distortion.

  • B. linearity.

  • C. phase shifting.

  • D. dynamic range

Explanation

Question 27 of 89

1

At a fixed test frequency, in which of the following materials will the eddy current penetration be greatest?

Select one of the following:

  • A. Aluminum (35 percent IACS conductivity)

  • B. Brass (15 percent IACS conductivity)

  • C. Copper (95 percent IACS conductivity)

  • D. Lead (7 percent IACS conductivity)

Explanation

Question 28 of 89

1

The heating effect in magnetic materials caused by the work
required to rotate magnetic domains can be eliminated by:

Select one of the following:

  • A. increasing the rate of displacement of the specimen through the coil.

  • B. magnetically saturating the test specimen.

  • C. decreasing the rate of displacement of the test specimen through the test coil.

  • D. testing in an air-conditioned room.

Explanation

Question 29 of 89

1

If the test frequency increases while the field strength is held constant, the surface eddy current density:

Select one of the following:

  • A. decreases.

  • B. increases.

  • C. remains the same.

  • D. could do any of the above.

Explanation

Question 30 of 89

1

As the fill factor decreases, the impedance variation of a
pickup coil produced by a given change in conductivity will:

Select one of the following:

  • A. increase.

  • B. remain the same.

  • C. decrease.

  • D. could do any of the above.

Explanation

Question 31 of 89

1

Which of the following would be easier to detect in tubing by the eddy current method using the self-comparison differential coil arrangement?

Select one of the following:

  • A. Gradual changes in diameter.

  • B. Gradual changes in conductivity.

  • C. Changes in temperature.

  • D. Short flaws.

Explanation

Question 32 of 89

1

The magnetic domains in an unmagnetized ferromagnetic material are:

Select one of the following:

  • A. arranged to facilitate the conduction of electrons.

  • B. randomly oriented and neutralize each other.

  • C. uniformly oriented.

  • D. create a major north and south pole in the material.

Explanation

Question 33 of 89

1

When a magnetic material is placed in a region of an applied magnetizing force (H), magnetic field (B) is developed in the material by means of:

Select one of the following:

  • A. induction.

  • B. conduction.

  • C. heat transfer.

  • D. magnetic domain transfer.

Explanation

Question 34 of 89

1

To eliminate any dependence upon the number of turns of a test coil, the inductance values of an impedance diagram are:

Select one of the following:

  • A. disregarded.

  • B. normalized.

  • C. corrected to a value of 1.

  • D. none of the above.

Explanation

Question 35 of 89

1

A term used to define a system which indicates only the magnitude of variations in the total coil impedance regardless of the phase or direction in which it occurs on an impedance plane is:

Select one of the following:

  • A. inductive reactance magnitude system.

  • B. feedback-controlled system.

  • C. impedance-magnitude system.

  • D. impedance vector analysis system.

Explanation

Question 36 of 89

1

When eddy current testing tubing with a system that includes a frequency discriminating circuit, which of the following variables would we classified as a high-frequency variable?

Select one of the following:

  • A. Small discontinuities.

  • B. Conductivity changes.

  • C. Diameter changes

  • D. Wall thickness variations.

Explanation

Question 37 of 89

1

A major problem associated with the eddy current test method is the:

Select one of the following:

  • A. inability of eddy current testing to accurately measure conductivity.

  • B. need to test at low speeds to prevent skipping.

  • C. large number of known or unknown variables which appear in the output indication.

  • D. inability of eddy current testing to detect small discontinuities.

Explanation

Question 38 of 89

1

The atoms of a metal showing magnetic characteristics are grouped into regions which are the smallest known permanent magnets. These regions are called:

Select one of the following:

  • A. lattice structures.

  • B. cells.

  • C. domains.

  • D. planetary spins.

Explanation

Question 39 of 89

1

When a coil's magnetizing force is applied to a ferromagnetic
material, the flux density in the material is:

Select one of the following:

  • A. less than the flux density generated by the test coil
    because of heat losses.

  • B. less than the flux density generated by the test coil
    because of resistivity.

  • C. the same as the flux density generated by the test coil.

  • D. greater than the flux density generated by the test coil.

Explanation

Question 40 of 89

1

The flux density in a magnetic material is usually designed by the:

Select one of the following:

  • A. Greek symbol “μ” (mu)

  • B. Greek symbol “∆” (delta)

  • C. letter B

  • D. letter H

Explanation

Question 41 of 89

1

The magnetizing force of an eddy current test coil is usually designated by the:

Select one of the following:

  • A. Greek symbol “μ” (mu)

  • B. Greek symbol “∆” (delta)

  • C. letter B

  • D. letter H

Explanation

Question 42 of 89

1

The thickness of nonconductive coatings on a conductive base can be most simply measured by:

Select one of the following:

  • A. observing the lift-off effect caused by the coating.

  • B. testing both sides of the specimen.

  • C. varying the current in the test coil.

  • D. varying the test frequency over a given range during the test.

Explanation

Question 43 of 89

1

The use of magnetic shielding around the exciting coil will
generally:

Select one of the following:

  • A. increase the magnetic field extension but decreases the eddy
    current penetration.

  • B. increase the magnetic field extension and eddy current
    penetration.

  • C. decrease the magnetic field extension but increase the eddy
    current penetration.

  • D. decrease the magnetic field extension and eddy current
    penetration.

Explanation

Question 44 of 89

1

Which of the following is not a factor that affects the
inductance of an eddy current test coil?

Select one of the following:

  • A. Diameter of coils.

  • B. Test frequency.

  • C. Overall shape of the coils.

  • D. Distance from other coils.

Explanation

Question 45 of 89

1

An out-of-phase condition between current and voltage:

Select one of the following:

  • A. can exist only in the primary winding of an eddy current
    coil.

  • B. can exist only in the secondary winding of an eddy current
    coil.

  • C. can exist in both the primary and secondary windings of an
    eddy current coil.

  • D. exists only in the test specimen.

Explanation

Question 46 of 89

1

A term used to define a surface coil mounted so that the coil can be rotated about the circumference of a test specimen is:

Select one of the following:

  • A. bobbin coil.

  • B. encircling coil.

  • C. spinning coil.

  • D. gap coil.

Explanation

Question 47 of 89

1

A term used to define an eddy current test coil which uses magnetic material to purposely shape the magnetic field is:

Select one of the following:

  • A. bobbin coil.

  • B. encircling coil.

  • C. spinning coil.

  • D. gap coil.

Explanation

Question 48 of 89

1

The vector-point, ellipse, and linear time-base methods are all subdivisions of the:

Select one of the following:

  • A. impedance method of testing.

  • B. the modulation analysis method of testing.

  • C. the phase analysis method of testing.

  • D. none of the above.

Explanation

Question 49 of 89

1

It is frequently possible to separate the conductivity variable from the permeability and dimensional variables when using:

Select one of the following:

  • A. the vector-point method of testing.

  • B. the ellipse method of testing.

  • C. the linear time-base method of testing.

  • D. any of the above methods of testing.

Explanation

Question 50 of 89

1

When eddy current testing by the ellipse method, the normal indication when the test specimen and reference standard are the same is approximately:

Select one of the following:

  • A. a straight horizontal line on a cathode ray tube.

  • B. an ellipse on a cathode ray tube.

  • C. a null reading on a meter.

  • D. a clean base line on a strip chart.

Explanation

Question 51 of 89

1

When eddy current testing by the ellipse method, one variable may be indicated by the angle of the ellipse or straight line while another variable may be indicated by the:

Select one of the following:

  • A. brightness of the ellipse.

  • B. horizontal length of the straight line.

  • C. size of the ellipse opening.

  • D. sinusoidal shape of the waveform.

Explanation

Question 52 of 89

1

When eddy current testing by the linear time-base method, what is applied to the vertical deflection plates of a cathode ray tube when the test specimen and reference standard are the same and the balance controls are properly adjusted?

Select one of the following:

  • A. A sinusoidal wave in phase with the timing voltage.

  • B. A sinusoidal wave 90 degrees out of phase with the timing
    voltage.

  • C. A sawtooth waveform.

  • D. Zero net voltage.

Explanation

Question 53 of 89

1

When eddy current testing by the linear time-base method, what is applied to the vertical deflection plates of a cathode ray tube when a condition of unbalance exists between the test specimen and the reference standard?

Select one of the following:

  • A. A sinusoidal wave

  • B. A sawtooth wave

  • C. A square wave

  • D. No voltage

Explanation

Question 54 of 89

1

The conductivity value for a metal is a function of the:

Select one of the following:

  • A. heat treatment given the metal.

  • B. cold working performed on the metal.

  • C. aging process used on the metal.

  • D. all of the above.

Explanation

Question 55 of 89

1

The ratio of the specific diameter of a probe to the minimum discontinuity of interest should be:

Select one of the following:

  • A. less then 2.

  • B. greater than 2.

  • C. greater than 4.

  • D. greater than 10.

Explanation

Question 56 of 89

1

Which of the following materials would be more likely used as a mounting material for a probe coil?

Select one of the following:

  • A. Aluminum

  • B. Fiberglass

  • C. Copper

  • D. Steel

Explanation

Question 57 of 89

1

A term used to define a surface or internal rupture which is attributed to processing at too low a temperature or excessive working or metal movement during the forging, rolling, or extruding operation is:

Select one of the following:

  • A. cold shut.

  • B. microshrinkage.

  • C. burst.

  • D. inclusion.

Explanation

Question 58 of 89

1

A term used to define the timing relationships involved in alternating current signals is:

Select one of the following:

  • A. magnitude.

  • B. phase.

  • C. impedance.

  • D. reactance.

Explanation

Question 59 of 89

1

When eddy current testing a nonferrous material, the choice of test frequency is determined by the:

Select one of the following:

  • A. degree of phase discrimination required.

  • B. eddy current penetration needed.

  • C. rate of response required.

  • D. all of the above.

Explanation

Question 60 of 89

1

When testing ferrous materials, a small but detectable portion of the magnetic flux in the material will pass outside the metal when a surface discontinuity is encountered. This flux is called:

Select one of the following:

  • A. air flux.

  • B. leakage flux.

  • C. induced flux.

  • D. none of the above.

Explanation

Question 61 of 89

1

A term to define a property of a test system which enables the separation of signals due to discontinuities in the test specimen that are located in close proximity to each other is:

Select one of the following:

  • A. dynamic range.

  • B. sensitivity.

  • C. linearity.

  • D. discontinuity resolution.

Explanation

Question 62 of 89

1

A term used to define a material having a permeability less than that of a vacuum is:

Select one of the following:

  • A. diamagnetic.

  • B. ferromagnetic.

  • C. paramagnetic.

  • D. magnetic.

Explanation

Question 63 of 89

1

The inductive reactance of a coil is measured in units of:

Select one of the following:

  • A. mhos.

  • B. ohms.

  • C. henrys.

  • D. gauss.

Explanation

Question 64 of 89

1

Which of the following coil arrangements would eliminate or decrease the effects of minor variations in diameter, chemical composition, hardness, etc., which occur gradually along the length of a wire?

Select one of the following:

  • A. External reference differential

  • B. Self-comparison differential

  • C. Single coil absolute

  • D. Double coil absolute

Explanation

Question 65 of 89

1

Which of the following conditions are not important when
selecting specimens to be used as reference standards?

Select one of the following:

  • A. The specimen should be of the same size and shape as the piece to be tested.

  • B. The specimen should have the same heat treatment as the piece to be tested.

  • C. The surface finish of the specimen should be the same as the piece to be tested.

  • D. If the material is aluminum, the surface should be anodized.

Explanation

Question 66 of 89

1

An eddy current test coil's magnetic field intensity in air:

Select one of the following:

  • A. increases with distance outside the coil and varies across the diameter inside the coil.

  • B. decreases with distance outside the coil and varies across the diameter inside the coil.

  • C. decreases with distance outside the coil and is assumed to be constant across the diameter inside the coil.

  • D. increases with distance outside the coil and is assumed to be constant across the diameter inside the coil.

Explanation

Question 67 of 89

1

The circuits which make it possible to minimize the effect of signals caused by variables of no interest on the readout mechanism are based on differences in:

Select one of the following:

  • A. amplitude.

  • B. phase

  • C. frequency.

  • D. any one of a combination of the quantities listed above.

Explanation

Question 68 of 89

1

When a nonmagnetic rod is placed inside an eddy current test
coil:

Select one of the following:

  • A. the magnetic field generated by the coil is increased in
    intensity.

  • B. the distribution of eddy currents is uniform through the
    rod's cross section.

  • C. the distribution of eddy currents is at a maximum at the rod's
    surface, or near the surface, and decreases to essentially zero
    at the rod's center.

  • D. the temperature of the rod decreases.

Explanation

Question 69 of 89

1

The symbol commonly used to signify impedance is:

Select one of the following:

  • A. Z

  • B. X

  • C. R

  • D. Xc

Explanation

Question 70 of 89

1

A decrease in conductivity is equivalent to:

Select one of the following:

  • A. an increase in permeability.

  • B. an increase in resistivity.

  • C. a decrease in permeability.

  • D. a decrease in resistivity.

Explanation

Question 71 of 89

1

If the conductivity of a test part in an eddy current test coil decreases, the magnitude of the eddy currents at a given depth in the test specimen:

Select one of the following:

  • A. increases.

  • B. remains the same.

  • C. decreases.

  • D. may increase or decrease.

Explanation

Question 72 of 89

1

When the voltage applied to a circuit and the current through the circuit both reach their maximums and minimums at the same time, the voltage and current are:

Select one of the following:

  • A. additive.

  • B. in phase.

  • C. regenerative.

  • D. out of phase.

Explanation

Question 73 of 89

1

Which of the following is not a commonly used eddy current testing readout mechanism?

Select one of the following:

  • A. Signal generator.

  • B. Meter.

  • C. Cathode ray tube.

  • D. Strip-chart recorder.

Explanation

Question 74 of 89

1

Which of the following materials would have the highest resistivity value?

Select one of the following:

  • A. Aluminum with a 42 percent IACS rating.

  • B. Magnesium with a 37 percent IACS rating.

  • C. Cast steel with a 10.7 percent IACS rating.

  • D. Zirconium with a 3.4 percent IACS rating

Explanation

Question 75 of 89

1

The ratio of a material's flux density to a test coil's magnetizing force, (B/H), can be used to determine the
material's:

Select one of the following:

  • A. conductivity.

  • B. resistivity.

  • C. lift-off.

  • D. permeability.

Explanation

Question 76 of 89

1

The magnetic field generated by eddy currents induced in a test specimen:

Select one of the following:

  • A. opposes the magnetic field that induced the eddy currents.

  • B. reinforces the magnetic field that induced the eddy
    currents.

  • C. cancels the magnetic field that induced the eddy currents.

  • D. has no effect on the magnetic field that induced the eddy
    currents.

Explanation

Question 77 of 89

1

The impedance of a test coil usually can be represented by the vector sum of:

Select one of the following:

  • A. inductive reactance and resistance.

  • B. capacitive reactance and resistance.

  • C. inductive reactance and capacitive reactance.

  • D. inductance and capacitance

Explanation

Question 78 of 89

1

For age hardenable aluminum and titanium alloys, changes in hardness are indicated by changes in:

Select one of the following:

  • A. retentivity.

  • B. permeability.

  • C. conductivity.

  • D. magnetostriction.

Explanation

Question 79 of 89

1

The penetration of eddy currents in a conductive material is
decreased when:

Select one of the following:

  • A. test frequency or conductivity of the specimen is decreased.

  • B. test frequency is decreased or conductivity of the specimen is increased.

  • C. test frequency, conductivity of the specimen or permeability of the specimen are increased.

  • D. permeability of the specimen is decreased.

Explanation

Question 80 of 89

1

When the electrical current in an eddy current coil reverses
direction:

Select one of the following:

  • A. the direction of the eddy currents in a part remains the
    same.

  • B. the eddy currents in the test part will change phase by 45
    degrees.

  • C. the direction of the eddy currents in the part also
    reverses.

  • D. the eddy currents in the part remain the same.

Explanation

Question 81 of 89

1

When testing magnetic materials in an ac field, increasing the field strength:

Select one of the following:

  • A. has no effect.

  • B. increases eddy current penetration.

  • C. decreases eddy current penetration.

  • D. decreases eddy current penetration to some minimum value, and then increases it to its maximum value when the specimen becomes magnetically saturated.

Explanation

Question 82 of 89

1

Impedance diagrams have been mathematically derived and experimentally verified for materials of any conductivity and permeability having rectangular, cylindrical, or spherical symmetry. To test all specimens of similar geometry under the same condition, it is only necessary to choose a test frequency, f, so that frequency ratio f/fg lies at the same point on the impedance diagram for each specimen. This principle is based upon:

Select one of the following:

  • A. Ohm's Law.

  • B. Kirchoff's Law.

  • C. the Similarity Law.

  • D. none of the above.

Explanation

Question 83 of 89

1

To be useful, limit frequency equation must be:

Select one of the following:

  • A. used with their impedance diagrams.

  • B. used to determine their impedance diagrams.

  • C. both of these.

  • D. neither of these.

Explanation

Question 84 of 89

1

When a rod is placed in an encircling type of coil, the density of eddy currents will be the greatest:

Select one of the following:

  • A. at the surface.

  • B. at the center.

  • C. midway between the surface and the center.

  • D. none of the above.

Explanation

Question 85 of 89

1

The term fill factor applies to:

Select one of the following:

  • A. a surface coil.

  • B. coaxial cable.

  • C. an encircling coil.

  • D. all of the above.

Explanation

Question 86 of 89

1

An eddy current system using handling equipment with automatic marking of the defective areas primarily makes it possible to:

Select one of the following:

  • A. remove defective areas of the product, if desired.

  • B. eliminate test surface contamination.

  • C. allow an inexperienced operator to establish the defect cause.

  • D. pass rejectable material.

Explanation

Question 87 of 89

1

Two test coils are often used in a bridge circuit to:

Select one of the following:

  • A. eliminate skin effect.

  • B. determine the differences between a known standard sample.

  • C. increase the conductivity of the circuit.

  • D. decrease the system sensitivity.

Explanation

Question 88 of 89

1

When inspecting ferromagnetic materials, relatively low
frequencies are normally used because of the:

Select one of the following:

  • A. low penetrability of these materials.

  • B. higher resolution.

  • C. lower resolution.

  • D. higher penetrability of these materials.

Explanation

Question 89 of 89

1

In modulation analysis testing, which of the following would not modulate the test frequency applied to the test coil?

Select one of the following:

  • A. Discontinuities in the test specimen.

  • B. Dimension changes of the test specimen.

  • C. Chemical composition of the test specimen.

  • D. A filter in the test circuit.

Explanation

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