Preparatory Notes for ASNT NDT Level III Examination - Ultrasonic Testing, UT

191. The lack of parallelism between the entry surface and the back surface:
A. May result in a screen pattern that does not contain back reflection
indications
B. Makes it difficult to locate discontinuities that lie parallel to the entry
surface
C. Usually indicates that a porous condition exists in the metal
D. Decreases the penetrating power of the test
192. A discontinuity with a concave surface will:
A. Diffuse the sound energy throughout the part
B. Cause the reflected beam to focus at a point determined by the
curvature of the discontinuity
C. Cause mode reinforcement of the ultrasonic wave
D. Cause none of the above