Eddy Current Testing questions and
answers rated A+
In electromagnetic testing, which of the following is not a source of noise?
A. Geometrical changes.
B. Permeability variations within the test object.
C. Electrical interference.
D. Coil size. - ANS ✔✔D
The ratio of the response or amplitude from signals of interest to the response or amplitude of
indications that contain no useful information for the test being conducted is referred to as:
A. Aspect ratio.
B. Signal-to-noise ratio.
C. The conductivity-to-permeability ratio.
D. The reactance-to-Resistance ratio. - ANS ✔✔B
Which of the following is not a basic component of an eddy current test system?
A. Amplifier.
B. Sine wave generator.
C. Wear-resistance tape.
D. Filter. - ANS ✔✔C
,When conducting an eddy current test using a differential comparison coil arrangement that
compares an external reference standard with the test specimen, the system should be noted or
balanced:
A. With only the reference standard in one coil.
B. With the reference standard and one coil and an acceptable test specimen in the other coil.
C. With the reference standard in one coil and an unacceptable test specimen in the other coil.
D. With only the test specimen in one coil. - ANS ✔✔B
The impedance of a test coil will increase if the:
A. Test frequency increases.
B. Inductive reactance of the coil decreases.
C. Inductance of the coil decreases.
D. Resistance of the coil decreases. - ANS ✔✔A
Some of the products commonly tested using encircling coils are:
A. Rods, tubes, and wire.
B. Plate when volumetrically inspected.
C. Sheets and metallized foil.
D. Structural steel welds. - ANS ✔✔A
Which of the following would normally be considered the best fill factor when testing straight
tubing with an encircling or feedthrough coil?
A. 1.75 (175%)
, B. 0.95 (95%)
C. 0.50 (50%)
D. 0.25 (25%) - ANS ✔✔B
When a metal part is placed in an eddy current test coil, the impedance of the coil will be
changed by all of the following properties of the part except:
A. Conductivity.
B. Dimensions.
C. Permeability.
D. Non-conductive coating. - ANS ✔✔D
An eddy current test makes use of electrical current induced in a conductive article by:
A. Gamma rays.
B. An alternating magnetic field.
C. A Piezoelectric electric force.
D. A decay process. - ANS ✔✔B
The conductivity of a material can be altered by changing the:
A. Amount of paint on the parts surface.
B. Chemistry of the part.
C. Length of the part.
D. Volume of the part. - ANS ✔✔B
answers rated A+
In electromagnetic testing, which of the following is not a source of noise?
A. Geometrical changes.
B. Permeability variations within the test object.
C. Electrical interference.
D. Coil size. - ANS ✔✔D
The ratio of the response or amplitude from signals of interest to the response or amplitude of
indications that contain no useful information for the test being conducted is referred to as:
A. Aspect ratio.
B. Signal-to-noise ratio.
C. The conductivity-to-permeability ratio.
D. The reactance-to-Resistance ratio. - ANS ✔✔B
Which of the following is not a basic component of an eddy current test system?
A. Amplifier.
B. Sine wave generator.
C. Wear-resistance tape.
D. Filter. - ANS ✔✔C
,When conducting an eddy current test using a differential comparison coil arrangement that
compares an external reference standard with the test specimen, the system should be noted or
balanced:
A. With only the reference standard in one coil.
B. With the reference standard and one coil and an acceptable test specimen in the other coil.
C. With the reference standard in one coil and an unacceptable test specimen in the other coil.
D. With only the test specimen in one coil. - ANS ✔✔B
The impedance of a test coil will increase if the:
A. Test frequency increases.
B. Inductive reactance of the coil decreases.
C. Inductance of the coil decreases.
D. Resistance of the coil decreases. - ANS ✔✔A
Some of the products commonly tested using encircling coils are:
A. Rods, tubes, and wire.
B. Plate when volumetrically inspected.
C. Sheets and metallized foil.
D. Structural steel welds. - ANS ✔✔A
Which of the following would normally be considered the best fill factor when testing straight
tubing with an encircling or feedthrough coil?
A. 1.75 (175%)
, B. 0.95 (95%)
C. 0.50 (50%)
D. 0.25 (25%) - ANS ✔✔B
When a metal part is placed in an eddy current test coil, the impedance of the coil will be
changed by all of the following properties of the part except:
A. Conductivity.
B. Dimensions.
C. Permeability.
D. Non-conductive coating. - ANS ✔✔D
An eddy current test makes use of electrical current induced in a conductive article by:
A. Gamma rays.
B. An alternating magnetic field.
C. A Piezoelectric electric force.
D. A decay process. - ANS ✔✔B
The conductivity of a material can be altered by changing the:
A. Amount of paint on the parts surface.
B. Chemistry of the part.
C. Length of the part.
D. Volume of the part. - ANS ✔✔B
