UT Level 1 Flashcards
- A second name for a compressional wave is:
a. Lamp wave
b. Shear Wave
c. Longitudinal wave
d. Transverse wave
C. Longitudinal Wave
A second name for Rayleigh Waves is:
a. Shear waves
b. Longitudinal Waves
c. Transvese waves
d. Surface waves
d. Surface Waves
A material used between the face of a search unit and the test surface to permit or improve the transmission of ultrasonic vibrations from the search unit to the material being tested is called:
a. Wetting agent
b. Couplant
c. Acoustic transmitter
d. Lubricant
b. Couplant
The piezoelectric material in a search unit or probe which vibrates to produce ultrasonic waves is called:
a. A backing material
b. A lucite wedge
c. A crystal
d. A Couplant
c. A Crystal
The number of complete waves which pass a given point in a given period of time (usually a second) is referred to as the :
a. Amplitude
b. Pulse length
c. Frequency of a wave motion
d. Wavelength of a wave motion
c. Frequency of a wave motion
When the motion of the particles of a medium are parallel to the direction of wave motion, the wave being transmitted is called a:
a. Longitudinal wave
b. Shear wave
c. Surface wave
d. Lamb wave
a. Longitudinal wave
The number 25 million cycles per second can also be stated as:
a. 25 kHz
b. 2500 kHz
c. 25 MHz
d. 25 uhz
c. 25 MHz
A term used in ultrasonic’s to expresss the speed at which sound waves pass through various substances is:
a. Frequency
b. Velocity
c. Wave length
d. None of the above
b. Velocity
An ultrasonic testing technique in which the transducer (crystal) is at an angle to the test surface is called:
a. Angle beam testing
b. Immersion testing
c. Contact testing
d. Through-transmission testing
a. Angle beam testing
Most commercial ultrasonic testing is accomplished using frequencies betweeen:
a. 1-25 kHz
b. 1-25 MHz
c. 1 - 1000 kHz
d. 15 - 100 MHz
b. 1 - 25 MHz
Which of the following test frequencies would generally provide he best penetration in a 300 mm thick specimen of the course-grained steel?
a. 1.0 MHz
b. 2.25 MHz
c. 5.0 MHz
d. 10 MHz
a. 1.0 MHz
All other factors being equal, which of the following modes of vibration has the greatest velocity?
a. Shear wave
b. Transverse wave
c. Surface wave
d. Longitudinal wave
d. Longitudinal wave
Sound waves of a frequency beyond the hearing range of the human ear are referred to as ultrasonic waves or vibration, and the term embraces alll vibrational waves of a frequency great than approximately:
a. 20 000 hertz (Hz)
b. 2 megahertz (MHz)
c. 2 kilohertz (kHz)
d. 200 kilohertz (kHz)
a. 20 000 hertz (Hz)
A disadvantage of using natural quartz crystals in a seach unit is:
a. It will dissolve in water
b. It is the least efficent generator of ultrasonic energy of all commonly used materials
c. it is mechanically and electrically unstable
d. It easily loses its operating characteristics as it ages
It is the least effiecent generator of ultrasonic energy of all commonly used materials
An advantage of using lithium sulfate in search units is :
a. It is one of the most efficient generators of ultrasonic enegy
b. It is one of the most effiecent receivers of ultrasonic energy
c. It is insoluble
d. It can withstand temperatures as high at 700’C
b. It is one of the most efficient receivers of ultrasonic energy
Which of the following search units would contain the thinnest quartz crystal?
a. A 1 MHz search unit
b. A 5 MHz search unit
c. A 15 MHz search unit
d. A 25 MHZ search unit
d. A 25 MHz search unit
Note: The thinner the crystal the higher the frequency
A material that converts electrical energy to or mechanical enegy or converts mechanical energy to the electrical energy is called:
a. Piezoelectic
b. Component
c. Attenuative
d. Ultrasonic
A. Piezoelectic
The Number 100,000 Hz can be written:
a. 10 kHz
b. 100 kHz
c. 100 MHz
d. 1000 kHz
b. 100 kHz
A general term applied to all cracks, inclusions, blow holes, etc. Which cause a reflection of sonic energy is:
a. A disperser
b. A discontinuity
c. A attenuator
d. A refractor
b. A discontinuity
Which of the following search units (probes) would contain the thickest quartz crystal?
a. A 1 MHz search unit
b. A 5 MHz search unit
c. A 15 MHz search unit
d. A 25 MHz search unit
a. A 1 MHz search unit
Note: Lower frequecy the thicker the crystal
The amount of energy reflected from a discointinuity will be dependent on:
a. The size of the discontinuity
b. The orientation of the discontinuty
c. The type of the discontinuity
d. All of the above
d. All of the above
Which of the following can occur when an ultrasonic beam reaches the interface of two dissimilar materials?
a Reflection
b. Refraction
c. Mode conversion
d. All of the above
d. All of the above
The phenomenon by which a wave strikes a boundary and changes the direction of its propagation is referred to as:
a. Divergence
b. Rarefaction
c. Angulation
d. Reflection
d. Reflection
Which of the following is the correct formula for determining near field?
a. NF = D^2 F/ 4V
b. NF = D^2V/4F
c. NF = 4V/D^2F
d. NF = 4F/ D^2 V
a. NF = D^2 F/ 4V
The near field effects of a contact transducer may be reduced by:
a. Increasing transducer frequency
b. use of smaller diameter transducer
c. using an apprpriate water path
d. use of a focused transducer
b. use of smaller diameter transducer
Calculate the near field of a 2.25 MHz., 12 mm diameter transducer used on a steel test piece that has a velocity of 5.90 km/sec.
a. 1.14 mm
b. 2.57 mm
c. 13.72 mm
d. 54.9mm
c. 13.72 mm
The angle at which 90 degree refraction of a shear wave is reached is called:
a. The angle of incidence
b. The first citical angle
c. The angle of maximum reflection
d. The second critical angle
d. The second critical angle
Where does the beam divergence occur?
a. In the near field
b. At the boundary of the near field and far field
c. at the face of the crystal
d. None of the above
b. At the boundary of the near field and far field
Which of the following is the correct formula for determining beam divergence:
a. sinØ = 1.22V/Df
b. sinØ= 1.22Df / V
c. cosØ = 1.22V / Df
d. tanØ = 1.22V / Df
a. sinØ= 1.22V/Df
Which of the following is the correct formula for wavelength?
a. Wavelength = Frequency / Velocity
b. Wavelength = Velocity X Frequency
c. Wavelength = Velocity / Frequency
d. Wavelength = Velocity + Frequency
c. Wavelength = Velocity / Frequency
Inspection of castings is often impractical because of :
a. extremely small grain structure
b. coarse grain structure
c. uniform flow lines
d. uniform velocity of sound
b. Coarse grain structure
Calculate the near field length for a transducer 12 mm in diameter, 2.5 Mhz, in a medium with a velocity of 6.0 km/s
a. 15.0 mm
b. 1.25 mm
c. 12.5 mm
d. 1.5 mm
a. 15.0 mm
The formula for acoustic impedance is :
a. Z= p - V
b. Z= P/V
c. Z= p X V
d. Z= p + V
c. Z= p X V
The angle at which 90 degree reraction of a longitudinal sound wave is reached is called:
a. The angle of Incidence
b. The first critical angle
c. The angle of maximum reflection
d. The second critical Angle
b. The First Critical angle
What is the angle of a plastic shoe to get the 1st critical angle in brass?
a. 54.8 Degrees
b. 75.7 Degrees
c. 65,4 Degrees
d. 37.2
37.2
A plastic shoe with an angle of 35 degrees produces a shear wave an angle of _____________ in steel?
a. 24 degrees
b. 44 degrees
c. 1.25 degrees
d. 15 degrees
b. 44 degrees
sin35/2.67=sinØ2/3.23
An angle of 20 degrees in water produces a shear wave at an agle of ____ in steel?
a. 25.4 degrees
b. 18.8 degrees
c. 37.6 degrees
d. 1.35 degrees
c. 37.6 degrees
An incident longitudinal wave, transmitted at an angle less than the first critical angle will generate:
a. Longitudinal and shear waves
b. Longitudinal and surface waves
c. Longitudinal waves only
d. Shear waves only
a. Longitudinal and shear waves
Refracted sound waves are calculated using which of the following formulas:
a. Snells Law
b. Huygens Principle
c. Creeping wave formula
d. Acoustic Impedance
a. Snells law
Which of the following crystals is a good reciever of sound
a. Barium Titanate
b. Dilythium crystals
c. Lithium Sulphate
d. Iridium Kryonic
c. Lithium Sulphate
Which of the following is a good transmitter of sound
a. Barium Titanate
b. Dilthium crystals
c. Lithium Sulphate
d. Irridium Kryonic
a. Barium Titanate
The phenomenon by which a wave strikes a bounday and changes the direction of its propagation is referred to as:
a. Divergence
b. Rarefaction
c. Angulation
d. Reflection
D. Reflection
A frequency increases in ultrasonic testing, the angle of beam divergence of a given diameter crystal:
a. Decreases
b. Remains unchanged
c. Increases
d. Varies uniformly through each wavelength
a. Decreases
A second name for a compressional wave is :
a. Lamb wave
b. Shear wave
c. Longitudinal wave
d. Transverse wave
c. Longitudinal wave
An incident longitudinal wave, transmitted at an angle less than the first critical angle will generate:
a. Longitudinal and shear waves
b. Longitudinal and surface waves
c. longitudinal waves only
d. shear waves only
a. Longitudinal and shear waves
A material used between the face of a search unit and the test surface to permit or improve the transmission of ultrasonic vibrations from the search unit to the material being tested is called:
a. wetting agent
b. Couplant
C. acoustic transmitter
d. lubricant
b. Couplant
Which of the following provides aplan view of the item under examination and displays depth as different colors?
a. A-Scan presentation
b. B- Scan presentation
c. C-Scan presentation
d. none of the above are adaptable for printed outs
c. C-scan Presentation
Another name for a Rayleigh wave is:
Surface waves
Viscosity of couplant chosen for a contact ultrasonic inspection will usually depend on :
a. probe size
b. nominal frequency
c. surface condtion
d. sensitivity required
c. Surface Condition
The indication on the display screen which represents the far boundary of the material being tested is called:
a. hash
b. the initial pulse
c. the “Main bang”
d. the back reflection
c. The Back Reflection
The critical angle refers to the
a. longitudinal waves angle
b. incident angle
c. refracted angle
d. reflected shear wave
b. Incident angle
Defects near the entry surface cannot always be accurately due to:
a. far-field effect
b. attenuation
c. test system recovery time ( Near Field)
d. Refraction
c. Test system recovery time ( Near Field)
Which of the following can occur when an ultrasonic beam reaches the interface of two dissimilar materials?
a, Reflection
b. Refraction
c. Mode conversion
d. All of the above
d. All of the above