MMET 402 EXAM 2 QUESTIONS,
ANSWERS, AND DETAILED
RATIONALES
Mode conversion, occurs when a sound wave encounters an interface
between materials of different acoustic impedance and:
a. One of the two materials is a liquid
b. The incident angle is greater than the first critical angle
c. The incident angle is greater than the second critical angle
d. The incident angle is not normal to the interface - CORRECT
ANSWER-d. The incident angle is not normal to the interface
Resolution generally increases:
a. With increased depth of a defect
b. With a decrease in the transducer frequency
c. When the transducer diameter is reduced
d. With an increase in transducer frequency - CORRECT ANSWER-d.
With an increase in transducer frequency
Shear waves do not propagate in:
a. Solids
b. Gases
,c. Liquids
d. Both B and C are correct - CORRECT ANSWER-d. Both B and C are
correct
Snell's Law describes the relationship between the sound velocity and:
a. The refracted angle of the wave
b. The reflected angle of the wave
c. Both A and B
d. None of the above - CORRECT ANSWER-c. Both A and B
Some transducers are specifically fabricated to be:
a. Better transmitters
b. Better receivers
c. Used in high temperature applications
d. All of the above - CORRECT ANSWER-d. All of the above
. Surface or Rayleigh waves travelling along the surface of relative thick
solid material, penetrate to a depth of approximately:
a. One wavelength
b. Two wavelengths
c. Three wavelengths
d. Infinite wavelengths - CORRECT ANSWER-a. One wavelength
The active element of most acoustic transducers used today is:
a. Lithium
b. Piezoelectric ceramic
, c. Sulfide
d. Quartz - CORRECT ANSWER-b. Piezoelectric ceramic
The ability to locate a small discontinuity is called:
a. Resolution
b. Sensitivity
c. Wavelength
d. Frequency - CORRECT ANSWER-b. Sensitivity
The ability to locate discontinuities that are close together within the
material is called:
a. Resolution
b. Sensitivity
c. Effectiveness
d. Phase delay - CORRECT ANSWER-a. Resolution
The act of evaluating and adjusting the precision and accuracy of the
measurement equipment is called:
a. Standardization
b. Calibration
c. Accuracy
d. Tuning - CORRECT ANSWER-b. Calibration
The area in front of a transducer where there are extensive fluctuations in
the sound field is called the:
a. Far field zone
ANSWERS, AND DETAILED
RATIONALES
Mode conversion, occurs when a sound wave encounters an interface
between materials of different acoustic impedance and:
a. One of the two materials is a liquid
b. The incident angle is greater than the first critical angle
c. The incident angle is greater than the second critical angle
d. The incident angle is not normal to the interface - CORRECT
ANSWER-d. The incident angle is not normal to the interface
Resolution generally increases:
a. With increased depth of a defect
b. With a decrease in the transducer frequency
c. When the transducer diameter is reduced
d. With an increase in transducer frequency - CORRECT ANSWER-d.
With an increase in transducer frequency
Shear waves do not propagate in:
a. Solids
b. Gases
,c. Liquids
d. Both B and C are correct - CORRECT ANSWER-d. Both B and C are
correct
Snell's Law describes the relationship between the sound velocity and:
a. The refracted angle of the wave
b. The reflected angle of the wave
c. Both A and B
d. None of the above - CORRECT ANSWER-c. Both A and B
Some transducers are specifically fabricated to be:
a. Better transmitters
b. Better receivers
c. Used in high temperature applications
d. All of the above - CORRECT ANSWER-d. All of the above
. Surface or Rayleigh waves travelling along the surface of relative thick
solid material, penetrate to a depth of approximately:
a. One wavelength
b. Two wavelengths
c. Three wavelengths
d. Infinite wavelengths - CORRECT ANSWER-a. One wavelength
The active element of most acoustic transducers used today is:
a. Lithium
b. Piezoelectric ceramic
, c. Sulfide
d. Quartz - CORRECT ANSWER-b. Piezoelectric ceramic
The ability to locate a small discontinuity is called:
a. Resolution
b. Sensitivity
c. Wavelength
d. Frequency - CORRECT ANSWER-b. Sensitivity
The ability to locate discontinuities that are close together within the
material is called:
a. Resolution
b. Sensitivity
c. Effectiveness
d. Phase delay - CORRECT ANSWER-a. Resolution
The act of evaluating and adjusting the precision and accuracy of the
measurement equipment is called:
a. Standardization
b. Calibration
c. Accuracy
d. Tuning - CORRECT ANSWER-b. Calibration
The area in front of a transducer where there are extensive fluctuations in
the sound field is called the:
a. Far field zone
