Which of the following frequencies is in the infrasound range?

1.. Propagation speed less than that of soft tissue will place reflectors that are too:

 

a. deep

b. medial

c. lateral

d. superficial

2. To overcome range ambiguity, the:

a. imaging depth should be increased

b. Reynolds number should be reduced

c. pulse repetition period should be reduced

d. pulse repetition frequency should be reduced

3. Steering of the sound beam is accomplished by:

a. reducing the pulse repetition frequency

b. altering the frequency with increasing depth

c. emitting pulses from different starting points

d. altering the electronic excitation of the elements

4. Which of the following techniques provides quantitative data?

a. amplitude mode

b. duplex imaging

c. spectral analysis

d. color flow imaging

5. Which of the following structures demonstrates the highest attenuation coefficient?

a. fat

b. air

c. liver

d. muscle

6. The range of frequencies contained in a pulse is termed the:

a. spectrum

b. bandwidth

c. harmonics

d. resonant frequencies

7. Which of the following frequencies is in the infrasound range?

a. 10 Hz

b. 25 Hz

c. 10 kHz

d. 25 kHz

8. Which of the following techniques uses separate transmitter and receiver elements?

a. duplex imaging

b. motion mode

c. real-time imaging

d. continuous wave Doppler

9. The majority of imaging artifacts are likely a result of:

a. operator error

b. system assumptions

c. weakly attenuating structures

d. strongly attenuating structures

10. Structures within the focal zone may display an improper

a. size

b. location

c. brightness

d. resolution

 

 

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