ARDMS SPI Practice Questions with 100%
Correct Answers
What are synonyms of half-value layer?
Penetration depth, depth of penetration, half-boundary layer
What does the half-value layer thickness depend on?
The medium and the frequency of sound
If there is a thin half-value, there is a _____ frequency sound and a media with _____
attenuation rate.
High, high
If there is a thick half-value, there is a ____ frequency sound and a media with ____
attenuation rate.
Low, low
What is impedance?
The acoustic resistance to sound traveling in a medium
impedance (rayls) =
Density (kg/m^3) x prop. speed (m/s)
What is impedance determined by?
The medium
What is a synonym to impedance?
Characteristic impedance
,Name three components of attenuation.
Absorption, reflection, and scattering
As the path length increases, the attenuation of ultrasound in soft tissue __________.
Increases
Attenuation in lung tissue is __________ than attenuation in soft tissue.
Greater
Attenuation in bone is __________ than attenuation in soft tissue.
Greater
Attenuation in air is ________ than attenuation in soft tissue.
Greater
What are the units of attenuation?
decibels (dB)
T or F. In a given medium, attenuation is unrelated to speed of sound.
True (attenuation and propagation speed are unrelated)
What is the relationship between ultrasound frequency and the attenuation coefficient
in soft tissue?
In soft tissue, the attenuation coefficient in dB per centimeter is approximately one half of
ultrasonic frequency in MHz
What are the units of the half-value layer thickness?
Distance; centimeters
, As frequency decreases, depth of penetration _________.
Increases
As path length increases, the half boundary layer __________.
Remains the same
Impedance is a characteristic of ___________.
Only the medium
As the path length increases, the attenuation coefficient of ultrasound in soft tissue
__________.
Remains the same
Acoustic impedance = ________ x _____________.
Impedance = density (kg/m^3) x propagation speed (m/s)
Two media A and B have the same densities. The speed of sound in medium A is 10%
higher than in medium B. Which medium has the higher acoustic impedance?
Medium A
Impedance is important in _______ at boundaries.
Reflections
Which is better to use while examining a carotid artery., a 7.5 or 3.0 MHz transducer?
7.5 MHz transducer (superficial)
What are the three types of angles?
Correct Answers
What are synonyms of half-value layer?
Penetration depth, depth of penetration, half-boundary layer
What does the half-value layer thickness depend on?
The medium and the frequency of sound
If there is a thin half-value, there is a _____ frequency sound and a media with _____
attenuation rate.
High, high
If there is a thick half-value, there is a ____ frequency sound and a media with ____
attenuation rate.
Low, low
What is impedance?
The acoustic resistance to sound traveling in a medium
impedance (rayls) =
Density (kg/m^3) x prop. speed (m/s)
What is impedance determined by?
The medium
What is a synonym to impedance?
Characteristic impedance
,Name three components of attenuation.
Absorption, reflection, and scattering
As the path length increases, the attenuation of ultrasound in soft tissue __________.
Increases
Attenuation in lung tissue is __________ than attenuation in soft tissue.
Greater
Attenuation in bone is __________ than attenuation in soft tissue.
Greater
Attenuation in air is ________ than attenuation in soft tissue.
Greater
What are the units of attenuation?
decibels (dB)
T or F. In a given medium, attenuation is unrelated to speed of sound.
True (attenuation and propagation speed are unrelated)
What is the relationship between ultrasound frequency and the attenuation coefficient
in soft tissue?
In soft tissue, the attenuation coefficient in dB per centimeter is approximately one half of
ultrasonic frequency in MHz
What are the units of the half-value layer thickness?
Distance; centimeters
, As frequency decreases, depth of penetration _________.
Increases
As path length increases, the half boundary layer __________.
Remains the same
Impedance is a characteristic of ___________.
Only the medium
As the path length increases, the attenuation coefficient of ultrasound in soft tissue
__________.
Remains the same
Acoustic impedance = ________ x _____________.
Impedance = density (kg/m^3) x propagation speed (m/s)
Two media A and B have the same densities. The speed of sound in medium A is 10%
higher than in medium B. Which medium has the higher acoustic impedance?
Medium A
Impedance is important in _______ at boundaries.
Reflections
Which is better to use while examining a carotid artery., a 7.5 or 3.0 MHz transducer?
7.5 MHz transducer (superficial)
What are the three types of angles?