UT-CW-02

best describes what term “Infrasound”?

• Sound waves with a frequency below 16 Hz

• Sound waves with a frequency above 16 Hz

• Sound waves with a frequency below 20 Hz

• Sound waves with a frequency above 20 Hz

type of display does a digital flaw detector most commonly use ?

component of the ultrasonic test equipment is responsible for the production of the ultrasonic vibrations?

a. OPT

b. Probe

c. Flaw Detector

d. Calibration block

Two types properties of a material, when combined have the most measurable effect on the sound wave velocity

• density

• grain size and surface condition

• elasticity

• all of above

define refraction in UT ?

• opposite to fraction

• bending of energy around the tip of a narrow reflector

• change of direction of the ultrasound beam passing from one medium to another

• reflection of the ultrasound beam

what accurately describe about sound? (3 types of vibrations )

Answer explanation

audible mechanical vibrations,

ultrasound mechanical vibrations,

infrasound mechanical vibrations.

what wavelength of ultrasound in a material calculated by?

• dividing material velocity by sound frequency

• dividing sound frequency by material velocity

• multiplying material velocity by sound frequency

• multiplying sound frequency by material velocity

What is the effect on sound beam near zone length, in the same material, when changing to a probe with the same diameter but a LOWER frequency?

• the length increase

• the length decrease

• all above

What is the effect on sound beam near zone length, in the same material, when changing to a probe with the same diameter but with LARGER frequency?

• the length increase

• the length decrease

• probe diameter has no effect on near zone length

• all above

which zones is zone of the ultrasound beam do the signal amplitudes become unreliable for comparing defect sizes. State the answer

• dead zone

• near zone

• far zone

• fraunhoffer zone