workbook

Question 0

HOw much bigger is a billion than a million?

a. 10 times
b. 100 times
c. 1,000 times
d. 500 times

Answer 0

C

Question 1

How many hertz is 3 MHz?

a. 3,000,000
b. 3,000
c. 333
d. 0.003

Answer 1

A

Question 2

How many milliliters are contained in a jar filled with 5 liters of fluid?

a. 5
b. 5,000
c. 500
d. 0.005

Answer 2

b

Question 3

How many liters are in 80 ml of fluid?

a. 8
b. 80
c. 0.008
d. 0.080

Answer 3

d

Question 4

What are the units of power?

Watts

Answer 4

Watts

Question 5

What are the units of intensity?

watts/cm2

Answer 5

watts/cm2

Question 6

If frequency of sound is doubled, what happens to wavelength?

Wavelength is halved

Answer 6

wavelength is halved

Question 7

The power of a system is at 100% and this is 0 dB. What is the dB change when the system’s power is 50%?

a. -10 dB
b. -50 dB
c. -3 dB
d. 3dB
e. 50 dB

Answer 7

The system’s power has been halved, -3 dB means half

Question 8

The power of a system is at 100% and this is 0dB. The system is changed to -6dB. what is the system’s power?

a. 100%
b. 75%
c. 50%
d. 25%
e. 6%

Answer 8

d. -6dB means one quarter (1/2 x 1/2 = 1/4).

Question 9

A 3MHz sound beam travels through two media. It attenuates 5dB in medium A and 6dB in medium B. What is the total attenuation that the sound beam undergoes as it travels through both media?

a. 6dB
b. 11 dB
c. 3dB
d. 15 dB

Answer 9

B. As sound travels, attenuation simply adds, just like tolls add when you travel on the highway

Question 10

• A 10 MHz sound beam travels through two media. It attenuates 5dB in medium B> What is the total attenuation that the sound beam undergoes as it travels throughout both media?

a. 6 dB
b. 10 dB
c. 16 dB
d. 15 dB

Answer 10

a. As sound travels, attenuation simply adds, just like tolls add when you travel on the highway

Question 11

• A 3 MHz sound beam travels 10cm, 6 cm in medium A and 4cm in medium B. The total attenuation is 14dB. If the sound beam attenuated 4dB in medium A, then how much attenuation occurred in medium B?

a. 2 dB
b. 14dB
c. 10dB
d. Cannot be determined

Answer 11

C. As sound travels, attenuation simply adds, just like tolls add when you travel on the highway, If 4dB of attenuation occurred in Medium A, then 10 dB must occur in Medium B. This would make the total attenuation 14 dB, as is given in the problem.

Question 12

Hint:

AS A GENERAL RULE, THERE ARE ONLY TWO MATHEMATICAL OPERATIONS THAT ARE DONE WITH dBs-ADD THEM OR SUBTRACT THEM

Answer 12

ADD OR SUBTRACT DECIBELS.

Question 13

In soft tissue, attenuation coefficient is directly related to ____.

Frequency

Answer 13

Frequency (If frequency doubles, attenuation coefficient will double)

Question 14

Rayleigh scattering is related to ___.

Frequency

Answer 14

Frequency (If frequency doubles, Rayleigh scattering increases by a factor of 16, 2x2x2x2=16)

Question 15

Sound wave strikes a boundary at normal incidence. The impedances of the two media are identical. what percentage of the sound wave is refracted?

a. 100%
b. 75%
c. 0%
d. 25%
e. 90%

Answer 15

C. *Remember, refraction requires oblique incidence

Question 16

Which of these media has the greatest attenuation and the SLOWER speed?

a. bone
b. tendon
c. fat
d. air

Answer 16

d

Question 17

Which of these media has the greatest attenuation and the FASTEST speed?

a. bone
c. tendon
c. lung
d. fat
e. air

Answer 17

a

Question 18

Which of the following describes the physics of refraction mathematically?

a. Bernoulli’s principle
b. Snell’s law
c. Pouiseulle’s law
d. Murphy’s law
e. Bernoulli’s law

Answer 18

B

Question 19

When a transducer is covered with a sterile cover with gel on the inside, what can the transducer not come into contact with in order to create an image?

a. gel
b. water
c. talcum powder
d. sterile liquid
e. lubricating gel

Answer 19

c. Talcum powder

Question 20

A sound beam is created by a round PZT crystal with a diameter of 10mm. The focal depth of the sound beam is 8cm. What is the diameter of the sound beam at a depth of 8cm?

a. 8 cm
b. 3 mm
c. 5 mm
d. 4 mm

Answer 20

c

Question 21

A sound beam is created by a round PZT crystal with a diameter of 10mm. The focal depth of the sound beam is 8cm. What is the diameter of the sound beam at a depth of 8cm?

a. the same as the TX diameter
b. 3/4 the TX diameter
c. Half the TX diameter
d. 4 mm

Answer 21

a

Question 22

Which of the following TX will have the POOREST axial resolution?

a. 1.7 MHx & 4 cycles per pulse
b. 2.6 MHz & 3 cycles per pulse
c. 1.7 MHz & 5 cycles per pulse
d. 2.6 MHz & 2 cycles per pulse

Answer 22

C. this is the longest pulse. It has the lowest frequency and the most cycles/pulse

Question 23

Which of the following TX has the BEST axial resolution?

a. 1.7 MHz and 4 cycles per pulse
b. 2.6 MHz and 3 cycles per pulse
c. 1.7 MHz and 5 cycles per pulse
d. 2.6 MHz and 2 cycles per pulse

Answer 23

d This is the shortest pulse, highest frequency and the fewest cycles/pulses

Question 24

How can lateral resolution at a given depth be estimated? a. use digital calipers to measure the image distance between two reflectors separated by 10 cm in a range. b. scan a specular reflector with perpendicular beam incidence, using two different gain settings c. determine the maximum depth of penetration in a tissue-mimicking phantom d. measure the largest dimension on the image size of a point reflector

Answer 24

d. measure the largest dimension on the image size of a point reflector. EXPLANATION: A point reflector is similar to a tiny dot that reflects sound. Since Lateral resolution is not as good as axial resolution, the reflection from this dot will be wider than it is long. Thus, the largest dimension is the width of the sound beam, and is the Lateral resolution

Question 25

All of these decrease Temporal resolution except: a. lower frame rate b. deeper imaging c. multi-focus imaging d. narrower sector

Answer 25

d

Question 26

A sonographer adjusts an ultrasound machine to double the depth of view from 5cm to 10cm. If the frame rate remains the same, which one of the following also changed? a. increased line density b. wider sector c. multi-focus imaging turned on d. narrower sector

Answer 26

d

Question 27

A sonographer, using a Phased array ultrasound system, turns off the multi-focus feature. What is the most likely consequence of this action? a. the frame rate decreases b. the temporal resolution degrades c. the imaging depth increases d. the temporal resolution improves

Answer 27

d

Question 28

A sonographer increases the line density from 1 line per degree of sector to 3 lines per degree of sector. What is the consequence of this action? a. the frame rate increases b. the temporal resolution decreases c. the imaging quality decreases d. the temporal resolution increases

Answer 28

b

Question 29

What is the frame rate if each image of ultrasound system is created in 0.02 seconds (1/50th sec)? a. 20 Hz b. 100Hz c. 50 Hz d. 15Hz

Answer 29

c

Question 30

What is the time needed to make a single image if the frame rate of ultrasound system is 20 Hz? a. 1 s b. 0.02 s c. 0.05 s d. 15 Hz

Answer 30

c

Question 31

What is the rationale for the ALARA principle? a. carbon footprint b. climate change c. patient exposure d. receiver gain

Answer 31

c

Question 32

True or False Harmonics are multiples of the transducer frequency

Answer 32

TRUE

Question 33

What feature does pulsed wave doppler have that continuous wave doppler does not?

Answer 33

Pulsed wave doppler has a receive gate that is adjusted by the sonographer