Correct Answers
Which of the following transducers will have the worst axial resolution?
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a. Vector array, 3 MHz
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b. Linear Sequential Array, 6 MHZ
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c. Linear Phased Array 7.5 MHZ
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d. Annular Array, 6 MHz - correct answer Vector array, 3 MHz
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A sound wave is traveling in the body and propagates from muscle to air. What percentage of the sound wave is
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most likely reflected at the muscle-air boundary?
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a. 0.5% d
b. 75% d
c. 25%
d
d. 5% d
e. 99% - correct answer 75%
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Which of the following lists is in decreasing order?
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a. mega, kilo, deca, milli, nano
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,b. centi, mill, kilo, mega, nano
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c. micro, milli, deci, kilo, mega
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d. micro, kilo, mega, deci, milli
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e. mega, micro, deci, milli, hecto - correct answer mega, kilo, deca, milk, nano
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During a diagnostic exam, which of these statements is most correct when describing the pulsed echo
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characteristics of an ultrasound system. d d d d
a. The listening time may be one-thousand times longer than the pulse duration.
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b. the pulse duration is longer than the pulse repetition period.
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c. The pulse duration is similar to the listening time.
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d. The duty factor has a value close to 1
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e. The pulse repitition period is similar to the period. - correct answer The listening time may be one-thousand
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times longer than the pulse duration.
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Which of the following parameters is determined by both the ultrasound system and the medium through
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which the sound travels? d d d
a. period
d
b. frequency
d
c. temperature
d
d. wavelength
d
e. velocity of the sound - correct answer wavelength
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You should be familiar with the formula L= C/F.
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What does "C" stand for in this equation?
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a. characteristic impedence
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b. density
d
c. compliance
d
d. compressability
d
e. propagation speed - correct answer propagation speed
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, Which of the following lists is in increasing order?
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a. mega, kilo, milli, nano, centi
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b. centi, milli, kilo, mega, nano
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c. micro, kilo, milli, deci, mega
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d. micro, milli, deci, kilo, mega
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e. mega, micro, deci, mill, hecto - correct answer micro, milli, deci, kilo, mega
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Which of the following statements about speed and attenuation are true?
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a. Attenuation through and propagation speed in a particular medium are unrelated to each other.
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b. When a sound beam travels faster in a medium, the attenuation is less.
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c. When a sound beam travels slower in a medium, the attenuation is more. - correct answer Attenuation
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through and propagation speed in a particular medium are unrelated to each other.
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A sonographer is scanning a patient with a 3 MHz probe and replaces it with a 6 MHz probe. All of the following
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statements are FALSE, except: d d d
a. The 6 MHz beam will travel at a lower speed than the 3 MHz beam
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b. The 6 MHz beam will travel faster than the 3 MHz beam
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c. The 3 MHz beam will have a higher frequency than the 6 MHz beam
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d. The 6 MHZ beam will have a longer period than the 3 MHz beam
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e. The 3 MHz beam will have a longer wavelength than the 6 MHz beam - correct answer The 3 MHz beam will
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have a longer wavelength than the 6 MHz beam
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Rank the following media in increasing order of propagation speed.
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a. muscle, liver, fat, bone, lung
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b. air, lung, fat, soft tissue, bone
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c. bone, muscle, fat, lung, air
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d. air, fat, bone, blood, water
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e. liver, kidney, fat, muscle, brain - correct answer air, lung, fat, soft tissue, bone
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