What pulse wave transducer displays a trapezoidal image?

1. Focusing of the sound beam:

 

a. decreases beam intensity

b. improves lateral resolution

c. increases specular reflections

d. creates a spacious sound beam over a specified area

2. As the transducer diameter increases, the:

a. near zone length decreases

b. thickness of the element decreases

c. intensity in the focal zone increases

d. divergence in the far field decreases

3. Holding a single image of sonographic informa­tion for display is termed a:

a. pixel

b. scan line

c. cine loop

d. freeze frame

4. The binary number 0010011 converts to which decimal equivalent?

a. 10

b. 19

c. 21

d. 35

5. The thickness of the matching layer is equal to:

a. the wavelength

b. twice the wavelength

c. one half of the wavelength

d. one quarter of the wavelength

6. Which of the following is most likely to improve axial resolution?

a. increasing the frame rate

b. decreasing the beam width

c. decreasing the angle of incidence

d. increasing the transducer frequency

7. What pulse wave transducer displays a trapezoidal image?

a. vector

b. linear

c. convex

d. endocavity

8.Heat sterilization of ultrasound transducers is not recommended, because:

a. the transducer’s stability decreases

b. heat will damage the electric cables

c. the piezoelectric properties will be lost

d. the transducer assembly cannot withstand the temperature

9. The formation of a beam from an aperture is explained by:

a. Snell’s law

b. ALARA principle

c. piezoelectric effect

d. Huygens principle

10. The Fresnel zone is another name for the:

a. far zone

b. dead zone

c. near zone

d. focal zone

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