BASIC EXAMINATION


1. Subsurface discontinuities are most likely to be discovered with magnetic particle testing in the following areas:
(a) Soft steels with high permeability
(b) Soft steels with low permeability
(c) Hardened steels with low permeability
(d) Hardened steels with high permeability

2. Which of the following benefits of magnetic particle testing is not true?
(a) Fast and simple to perform
(b) Can detect discontinuities filled with foreign material
(c) Most reliable for finding surface cracks in all types of material
(d) Works well through a thin coat of paint

3. Which of the following isn't a magnetic particle testing limitation?
(a) The type of materials which may be effectively tested
(b) The directionality of the magnetic field
(c) The need for demagnetization
(d) The ability to detect discontinuities filled with foreign material

4. The most effective NDT method for locating surface cracks in ferromagnetic materials
is:
(a) Ultrasonic testing
(b) Radiographic testing
(c) Magnetic particle testing
(d) Liquid penetrant testing




5. Which of the following may cause magnetic particle test indications?
(a) A joint between two ferromagnetic materials of different permeability
(b) A shrink fit joint in ferromagnetic materials
(c) A brazed joint in ferromagnetic materials
(d) All of the above

14. The reverse magnetising force necessary to remove a residual magnetic field from a
test piece after it has been magnetically saturated is called:
(a) Hysteresis
(b) Coercive force
(c) Demagnetising flux
(d) Reverse saturation

15. Magnetic lines of force enter and leave a magnet at:
(a) Saturation
(b) L/D ratios of greater than 4 to 1
(c) Flux concentration points
(d) Poles

16. The ease with which a magnetic field can be established in a test piece is called:
(a) Reluctance
(b) Retentivity
(c) Permeability
(d) Electromagnetism

17. Opposition to establishment of a magnetic field is called:
(a) Reluctance
(b) Retentivity
(c) Permeability
(d) Electromagnetism

18. The ability of a material to remain magnetic after the magnetising force is removed is
called:
(a) Reluctance
(b) Retentivity
(c) Permeability
(d) Electromagnetism

19. A magnetic field which is contained completely within the test piece is called a:
(a) Confined field
(b) Longitudinal field
(c) Circular field
(d) Saturated field

20. Which of the following produces a circular field?
(a) Coil
(b) Head shot
(c) Yoke
(d) All of the above