EXAM NEWEST 2025 ACTUAL
EXAM COMPLETE 170
QUESTIONS AND CORRECT
DETAILED ANSWERS (VERIFIED
ANSWERS) |ALREADY GRADED A+
Far boundary indication - ANSWER The indication on the instrument
display that represents the far boundary of the material being tested.
Immersion testing - ANSWER The position of the transducer is often
varied to transmit sound into the test part at various angles to the front
surface.
Acoustic impedance - ANSWER The product of the material density and
the velocity of sound within that material.
Straight beam contact transducer - ANSWER Consists of a case, a
crystal, a mount, backing, and acoustic lenses.
Immersion testing - ANSWER To remove the second water reflection
from between the entry surface signal and the first reflection, you should
increase the repetition rate, decrease the frequency, decrease the sweep
length, or increase the water path.
Refracted angle - ANSWER For a given incident angle, as the frequency
of the transducer increases, the refracted angle may increase, decrease,
stay the same, or cannot be determined.
Simultaneous wave generation - ANSWER Both longitudinal and shear
wave may be simultaneously generated in a second medium when the
angle of incidence is between normal and the first critical angle, between
the first and second critical angles, past the second critical angle, or only
the second critical angle.
, Sound beam behavior on concave surface - ANSWER In immersion
testing, when the sound beam strikes a concave surface, the sound beam
tends to converge, diverge, stay the same, or mode convert.
Depth of penetration - ANSWER Penetration of ultrasonic waves in a
material is normally the function of test frequency used. The greatest
depth of penetration is provided by a frequency of 1 MHz, 2.25 MHz, 5
MHz, or 10 MHz.
Efficient piezoelectric material - ANSWER Certain piezoelectric
materials exhibit better properties than others. The most efficient receiver
of ultrasonic energy is quartz, ceramic, barium titanate, or lithium sulfate.
Change in direction of propagation - ANSWER Refracted energy
assumes a new direction of propagation when the incident angle is
changed.
Energy loss during propagation - ANSWER The loss of energy as it
propagates through material is the result of beam interference, attenuation,
absorption, or reflection.
Coaxial cable - ANSWER The cable that connects the ultrasonic
instrument to the transducer is specially designed so that one conductor is
centered inside another.
Calibration - ANSWER The process of comparing an instrument or
device with a standard.
Compressional wave - ANSWER Another name for a longitudinal wave.
Rayleigh wave - ANSWER Another name for surface waves.
Couplant - ANSWER A material used between the face of a transducer
and the test surface to permit or improve the transmission of ultrasonic
vibrations.
Piezoelectric material - ANSWER The material in a transducer that
vibrates to produce ultrasonic waves.
Ultrasonic testing - ANSWER Testing of material where the transducer
is in direct contact with the material being tested.