A fault in magnetised material will best be detected when it lies in which of the following directions()
A. Parallel to the magnetic field
B. Perpendicular to the magnetising force
C. Parrallel to the magnetising current
D. Both perpendicular to the magnetic field and parrallel to the magnetising current
查看答案
What is the benefit of using visible dye penetrant over a fluorescent penetrant()
A. Easier to remove the excess background
B. Greater sensitivity is obtained
C. No special lighting is required
D. All the above are benefits
The magnetic flux lines which flow through a bar magnet form closed loops but can be broken by which of the following()
A change in permeability
B. A non metallic inclusion
C. A crack
D. None of the above will cause a break in a flux line
Which penetrant method is considered to be the most sensitive()
A. Visible solvent removable
B. Fluorescent water washable
C. Visible post emulsifiable
D. Fluorescent post emulsifiable
The contact angle for most commercial liquid penetrants has which of the values listed below()
A. Less than 5 degrees
B. Less than 10 degrees
C. Only needs to be less than 89 degrees
D. Only needs to be less than 89 degrees