How long will it take for sound to travel 5 cm round-trip in soft tissue?

1. The length of a pulse from beginning to end is termed the:

 

a. wavelength

b. pulse duration

c. spatial pulse length

d. pulse repetition period

2. In which of the following media does sound propagate the fastest?

a. air

b. bone

c. muscle

d. soft tissue

3. What is the frequency of a sound wave in soft tissue demonstrating a wavelength of 0.1 mm?

a. 2.0 MHz

b. 5.0 MHz

c. 7.5 MHz

d. 15.0 MHz

4. If the amplitude of a wave doubles, the intensity will:

a. double

b. quadruple

c. decrease by one half

d. decrease by one quarter

5. The time for one pulse to occur defines:

a. period

b. pulse duration

c. spatial pulse length

d. pulse repetition period

6. Which of the following is associated with a broader bandwidth?

a. a lower Q-factor

b. an increase in amplitude

c. a longer spatial pulse length

d. a decrease in the number of frequencies within the pulse

7. Regions of low density in a compression wave are termed:

a. cycles

b. bandwidth

c. rarefactions

d. compressions

8. Which of the following formulas calculates the duty factor?

a. power of the source divided by the area

b. pulse duration divided by the pulse repetition period

c. pulse repetition frequency divided by the pulse duration

d. frequency of the source multiplied by the prop­agation speed

9. Resistance to the propagation of sound through a medium defines:

a. reflection

b. attenuation

c. acoustic impedance

d. Rayleigh’s scatter

10. How long will it take for sound to travel 5 cm round-trip in soft tissue?

a. 26 ms

b. 30 ms

c. 65 ms

d. 130 ms

11. Overall compensation gain is set at 36 dB. If the gain is reduced by one half, what will the new gain be?

a. 18 dB

b. 25 dB

c. 30 dB

d. 33 dB

12. Attenuation occurring as sound propagates through each centimeter of soft tissue is equal to:

a. 1⁄2 operating frequency

b. attenuation coefficient 3 path length

c. medium density 3 propagation speed

d. 1⁄2 (propagation speed 3 round-trip time)

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