Lesson 1 Quiz UT COPY

Question 1

1. The velocity of sound in a material is dependent upon the ?

Answer 1

Material properties , The speed of sound in a material is mainly determined by the material’s properties, including its density and elasticity. While frequency and wavelength can change depending on the sound’s interaction with different media, the material’s prosperities directly affect the sound velocity.

Question 2

2. To vary or change the wavelength of sound being used to test a part, you would change the ?

Answer 2

Sound-Wave frequency, the wavelength of sound is inversely proportional to the frequency ( according to the e1quation, where is velocity and is frequency). Changing the frequency will directly alter the wavelength.

Question 3

3. Ultrasonic vibrations are commonly used to examine materials for ?

Answer 3

Discontinuities, Ultrasonic testing is widely used to detect discontinuities ( Flaws such as cracks or voids) in materials. This methos is effective because ultrasonic waves reflect off these defects, enabling their detection.

Question 4

4. The number of complete waves which pass a given point in a number of cycles per second is referred to as the?

Answer 4

Frequency of a wave motion, The frequency of a wave refers to how many compete cycles or waves pass a given point in a one second, measured in Herts (Hz).

Question 5

5. Sound waves with a frequency beyond human hearing range are referred to as ultrasonic waves or vibrations, and the terms embrace all vibrational waves of frequency greater than approximately?

Answer 5

20,000 Hz, Ultrasonic waves have frequencies above the human hearing range, which is typically around 20,000 Hz. Anything beyond this frequency is considered ultrasonic.

Question 6

6. When referring to ultrasonic testing, the term used to define the rate at which sound waves will pass through various substances is referred to as?

Answer 6

Velocity, Velocity refers to the speed at which sound travels throu8gh a material, which is crucial in ultrasonic testing for determining material thickness and identifying internal features.

Question 7

7. The total number of ultrasonic waves that pass a specific point in a second is know as the?

Answer 7

Frequency of wave motion, Frequency is the term that defines how many waves pass a given point per second, usually measured in Herts (Hz).

Question 8

8. Compute the wavelength of ultrasonic energy in steel at 5 MHz. Vs=5850m/s (V=A*f).

Answer 8

1.17mm, using the formula, where is the velocity (5950m/s) and is the frequency ( 5 MHz or 5 * 10^6Hz)

Question 9

9. One megahertz is best expressed by which of the following?

Answer 9

1*10^6 cycles /second, One megahertz (MHz) is equivalent to 1 million cycles per second, or.

Question 10

10. If the velocity of a longitudinal mode wave in a given material is 0.246 in./us ( 0.625 cm/us) at 0.5 in. (1.27 cm) below the surface, what is the velocity at 2 in. ( 5 cm) below the surface?

Answer 10

The same as the velocity at 0.5 in. (1.27 cm), In most materials, the velocity of sound waves is constant regardless of the depth, provided the material properties are homogeneous.

Question 11

11. Material particles in the path of a sound wave?

Answer 11

Do not travel with the wave but react to the wave energy , In sound wave propagation, particles oscillate or vibrate in response to the energy, but they do not move with the wave itself.

Question 12

12. It is the energy of the wave that moves through the material using the __________ as a means of passage.

Answer 12

Molecular structure, Sound wave propagate through the interaction between molecules within the materials structure.

Question 13

13. The wavelength of a given wave is from?

Answer 13

Trough to trough and is the same as the distance from peak to peak, Wavelength is measured from one identical point on a wave to the next, such as from trough to trough or peak to peak.

Question 14

14. If the frequency is higher, the wavelength?

Answer 14

Is shorter, Frequency and wavelength are inversely related. As frequency increases, the wavelength degreases.

Question 15

15. According to SNT-TC-1A, a Level 1 may?

Answer 15

Perform specific calibrations, In the context of ultrasonic testing certification, a Level 1 technician is typically limited to performing calibration and operating under the guidance of a Level 2 or 3.

Question 16

16. According to SNT-TC-1A, the certification of NDT personnel is the responsibility of ?

Answer 16

The employer, Certification responsibility for NDT personnel according to SNT-TC-1A lies with the employer, who must ensure that personnel meet the necessary qualifications.

Question 17

17. According To SNT-TC-1A:

Answer 17

The employer shall establish a written practice for qualification an certification of NDT personnel.

Question 18

18. According to SNT-TC-1A, a Level 3 who is certified in a specific method?

Answer 18

should have knowledge or other NDT methods. A level 3 technician is expected to be knowledgeable in other NDT methods beyond the specific one they are certified in. This broader understanding helps in interdisciplinary applications and oversight.

Question 19

19. According to SNT-TC-1A, a certified Level 1?

Answer 19

May record test results, A certified Level 1 technician has limited authority and may only accept or reject parts under supervision. However, they are responsible for recording test results as part of their role.

Question 20

20. Recommended practice SNT-TC-1A shall be used by the employer:

Answer 20

As a guide to establish a written practice that meets the needs of the empower and customer, SNT-TX-1A serves as a guideline for employers to create a written practice for qualification and certification. This practice should address both the employer’s and the customer’s.

Question 21

21. According to SNT-TC-1A, the employer:

Answer 21

May use the services of a Level 3 consultant, The employer is allowed to use the services of a level 3 consultant if they do not have a full -time level 3 employee. This allows flexibility in smaller companies or in special cases.

Question 22

22. According to SNT-TC-1A:

Answer 22

The employer shall establish a written practice for qualification and certification of NDT personnel, According to SNT-TC-1A, the responsibility for establishing a written practice for qualification and certification of NDT personnel lies with the employer. This written practice defines how personnel are trained, tested, and certified.

Question 23

23. The frequency of a wave describes?

Answer 23

The number of complete waves that pass a given point in a given period of time, Frequency is the measure of how many complete wave cycles pass a point in one second, ands is typically expressed in Hertz (Hz).

Question 24

24. What term is used to define the rate at which sound waves will pass through various substances?

Answer 24

Velocity, The term “velocity” refers to the speed at which sound waves travel through a material. This depends on factors such as the material’s density and elasticity.

Question 25

25. The factors that have the greatest effect on ultrasonic velocity are?

Answer 25

Material density, elasticity, and wave mode. The velocity of ultrasonic waves in a material is primarily influenced by its density, elasticity (stiffness), and the mode of the wave (such as longitudinal or shear).

Question 26

26. The velocity of sound in material s dependent?

Answer 26

Material and the type of wave being transmitted. The sound velocity is affected by the both the material through which the wave is propagating and the type of wave ( longitudinal, transverse, etc.). Different materials and wave types have distinct propagation speeds.