$($a$)$ Recommend two NDT testing methods capable of testing for defects and measuring the thickness of materials or coatings. $(6$ Marks$)$

$($b$)$ Describe the basic principle of the recommended test methods in $1($a$).(10$ marks$)$

$($c$)$ List three advantages and three disadvantages of the recommended methods in $1($a$).(12$ marks$)$

List and describe four types of ultrasonic wave propagation. $(8$ marks$)$

Distinguish between the nature of sound in fluids and solids. $(4$ marks$)$

Explain how ultrasound is generated. $(6$ marks$)$

Ultrasonic inspection techniques are commonly divided into three primary classifications. List and describe the three categories of ultrasonic inspection techniques. $(9$ marks$)$ nopmel Angl.boam.

Explain the role of piezoelectric materials in ultrasonic and list three examples of these materials. $(8$ marks$)$

List three characteristics of the specimen that affect the strength of the induced eddy currents. $(6$ marks$)-$ Magnticzine

List four advantages multi$-$frequency inspections. $(4$ marks$)$

sesentive

During data acquisition using eddy currentinspection, probes selection is critical.

$4$

What are the six factors to consider during probe selection? $(6$ Marks$)=>$ prohe the

$10.$Thermal science is very important in thermal infrared NDT method. What are the three heat transfer modes modes? $(3$ marks$)$

$11.$ What are the components of an Infrared $($IR$)$ imager? $(3$ Marks$)$

$12.$ Give a brief description of five typical industrial applications of thermal infrared testing. $(10$ marks$)$

$13.$ List five limitations of thermal infrared inspection. $(5$ marks$)$ y$-$ ib needs u shillad

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