Ultrasound Physics - Mock Exam
Questions for SPI
Which of the following statements about speed and attenuation are true?
a. Attenuation through and propagation speed in a particular medium are unrelated to
each other.
b. When a sound beam travels faster in a medium, the attenuation is less.
c. When a sound beam travels slower in a medium, the attenuation is more. -
✔️✔️Attenuation through and propagation speed in a particular medium are unrelated
to each other.
Which of the following lists is in increasing order?
a. mega, kilo, milli, nano, centi
b. centi, milli, kilo, mega, nano
c. micro, kilo, milli, deci, mega
d. micro, milli, deci, kilo, mega
e. mega, micro, deci, mill, hecto - ✔️✔️micro, milli, deci, kilo, mega
A sound wave is traveling in the body and propagates from muscle to air. What
percentage of the sound wave is most likely reflected at the muscle-air boundary?
a. 0.5%
b. 75%
c. 25%
d. 5%
e. 99% - ✔️✔️75%
Which of the following lists is in decreasing order?
a. mega, kilo, deca, milli, nano
b. centi, mill, kilo, mega, nano
c. micro, milli, deci, kilo, mega
d. micro, kilo, mega, deci, milli
e. mega, micro, deci, milli, hecto - ✔️✔️mega, kilo, deca, milk, nano
During a diagnostic exam, which of these statements is most correct when describing
the pulsed echo characteristics of an ultrasound system.
a. The listening time may be one-thousand times longer than the pulse duration.
b. the pulse duration is longer than the pulse repetition period.
c. The pulse duration is similar to the listening time.
d. The duty factor has a value close to 1
e. The pulse repitition period is similar to the period. - ✔️✔️The listening time may be
one-thousand times longer than the pulse duration.
,Which of the following parameters is determined by both the ultrasound system and the
medium through which the sound travels?
a. period
b. frequency
c. temperature
d. wavelength
e. velocity of the sound - ✔️✔️wavelength
You should be familiar with the formula L= C/F.
What does "C" stand for in this equation?
a. characteristic impedence
b. density
c. compliance
d. compressability
e. propagation speed - ✔️✔️propagation speed
A sonographer is scanning a patient with a 3 MHz probe and replaces it with a 6 MHz
probe. All of the following statements are FALSE, except:
a. The 6 MHz beam will travel at a lower speed than the 3 MHz beam
b. The 6 MHz beam will travel faster than the 3 MHz beam
c. The 3 MHz beam will have a higher frequency than the 6 MHz beam
d. The 6 MHZ beam will have a longer period than the 3 MHz beam
e. The 3 MHz beam will have a longer wavelength than the 6 MHz beam - ✔️✔️The 3
MHz beam will have a longer wavelength than the 6 MHz beam
Rank the following media in increasing order of propagation speed.
a. muscle, liver, fat, bone, lung
b. air, lung, fat, soft tissue, bone
c. bone, muscle, fat, lung, air
d. air, fat, bone, blood, water
e. liver, kidney, fat, muscle, brain - ✔️✔️air, lung, fat, soft tissue, bone
Which of the following intensities is most significant with regard to the study of
bioeffects?
a. SATP
b. SATA
c. SAPA
d. SPTA
e. SPTP - ✔️✔️SPTA
Which of the following terms does not belong with the others?
a. decreased depth of view
b. increased pulse duration
c. increased pulse repitition frequency
d. decreased pulse repitition period
, e. high duty factor - ✔️✔️increased pulse duration
What is a cyclical region of low density called?
a. compression
b. Pascal
c. rarefaction
d. density
e. impedence - ✔️✔️rarefaction
A sonographer adjusts the outout of an ultrasound system by increasing the amplitude
by a factor of three. Which of the following statements is true?
a. power is increased by a factor of three
b. wavelength is increased by a factor of nine
c. power is increased by a factor of nine
d. frequency in increased by a factor of three
e. period is decreased by a factor of three - ✔️✔️power is increased by a factor of nine
Sound travels at the same velocity in two different media. The density of Medium A is
half that of Medium B. Which of the following statements is true:
a. The impedence of Medium A is four times that of Medium B
b. The Reynold's number of Medium A is twice that of Medium B
c. The impedence of Medium A is twice that of Medium B
d. The resistive index of Medium A is twice that of Medium B
e. The impedence of Medium A is half that of Medium B - ✔️✔️The impedance of
Medium A is half that of Medium B
Which of the following mechanisms are not related to attenuation?
a. reflection
b. scattering
c. transmission
d. absorption
e. tissue heating - ✔️✔️transmission
In which of the following is the velocity of sound the lowest?
a. tendon
b. kidney
c. muscle
d. amniotic fluid
e. bone - ✔️✔️amniotic fluid
In soft tissue, which of the following is the best estimate for the attenuation coefficient of
a 4 MHz sound wave, with a PRF of 10 kHz?
a. 40 dB/cm
b. 5 dB/cm
c. 1.89 dB/cm
d. 2.5 dB/cm
