Top 1000+ Solved Non Destructive Testing and Evaluation MCQ Questions Answer
Q. Compared to the magnetic field strength at the outer surface, the magnetic field strength,at the centre of a hollow, nonmagnetic conductor carrying DC current is:
a. I/D
b. The same
c. Zero
d. Need more information to determine
Q. Which of the following describes the shape of particles used for dry magnetic particletesting?
a. Spherical
b. Angular
c. Elongated
d. Mixture of elongated and globular
Q. Which of the following particles would be most sensitive?
a. Wet
b. Dry
c. Depends on the test piece permeability
d. None of the above
Q. Which of the following colours is readily available for magnetic particle test powder?
a. Red
b. Gray
c. Black
d. All of the above
Q. A magnetic particle testing technique in which the test piece is magnetised andmagnetic particles applied after the magnetising force has been removed is called the:
a. Magnetic method
b. Continuous method
c. Residual method
d. Discontinuous method
Q. Which of the following characteristics would be most important in a test piece whichis to be tested using the residual method?
a. High rententivity
b. High permeability
c. Low reluctance
d. Low permeability
Q. The wet method is superior to dry particles for detecting:
a. Subsurface discontinuities
b. Fine surface cracks
c. Open surface cracks
d. None of the above
Q. Selection of magnetic particle colour is based on:
a. Optimum performance of magnetic particle/developer
b. Colour of inspection light available
c. Obtaining maximum contrast with the test piece background
d. Optimum colour response of the human eye
Q. The residual method is applicable to:
a. Surface discontinuities only
b. Subsurface discontinuities only
c. Either surface or subsurface discontinuities
d. All but tight surface cracks
Q. Highest sensitivity to fine surface cracks would be obtained by which of the followingtechniques?
a. Residual field, wet method
b. Residual field, dry method
c. Continuous field, wet method
d. Continuous field, dry method
Q. A residual field is always less than a continuous field because?
a. The magnetic field, as shown by a hysteresis curve, is zero when there is no magnetising force
b. The magnetic field, as shown by a hysteresis curve, is less when there is no magnetising force
c. The magnetic field, as shown by a hysteresis curve, is greater when there is no magnetising force
d. None of the above
Q. Where possible, circular magnetisation is preferable to longitudinal magnetizationbecause:
a. Less current is required
b. Stronger fields are obtained
c. Fewer confusing secondary poles are produced
d. None of the above is true
Q. Which of the following is a disadvantage of the dry method?
a. Ease of application with portable equipment
b. Superior sensitivity for fine surface cracks
c. Good particle mobility with AC and HWDC
d. Good sensitivity for subsurface discontinuities