ARDMS SPI LATEST EXAM B II 2026 FULL
SOLVED QUESTIONS ANSWERS ULTRASOUND
PRINCIPLES REVIEW SHEET
◉ What three things can occur when an ultrasonic beam reaches the
interface of two dissimilar materials?
Answer: reflection, refraction, mode conversion
◉ The acoustic impedance of a material is
Answer: equal to the product of density and velocity
◉ The average velocity of ultrasonic waves in soft tissue is
Answer: 1540 m/s
◉ True/False: Receiver-angle values in CW Doppler analysis do not
influence the final Doppler shift.
Answer: False
◉ Refraction occurs because of difference in ______ across an
interface between two materials
Answer: wave velocity
,◉ Reflection factor at an interface between two materials depends
primarily on the change in ______ across the interface.
Answer: acoustic impedance
◉ The velocity of sound waves is primarily dependent on
Answer: medium and mode of vibration
◉ Increasing the frequency of an ultrasonic longitudinal wave will
result in ______ in the velocity of that wave.
Answer: no change
◉ The change in direction of an ultrasonic beam, when it passes
from one medium to another, in which elasticity and density differ
from those of the first medium is called
Answer: refraction
◉ A long near zone can be obtained by
Answer: using a higher frequency transducer
◉ If a 2 MHz frequency is used in human soft tissue, the wavelength
is approximately
Answer: 0.75 mm
,◉ The ratio of particle pressure to particle velocity at a given point
within the ultrasonic field is
Answer: impedance
◉ What is the following formula used to determine?
(2 × velocity of reflector × original frequency) / velocity of sound
Answer: Doppler shift frequency
◉ The principle that states that all points on a wavefront can be
considered as point sources for the production of sperical secondary
wavelets was postulated by
Answer: Huygens
◉ A 10 dB difference in signal intensity is equivalent to a _______
difference.
Answer: tenfold
◉ The level below which signals are not transmitted through an
ultrasound receiver system is the
Answer: threshold, negative, reject level
◉ Gray-scale systems typically use _____ as a means of signal dynamic
range reduction.
, Answer: compression
◉ The strength of the echo is related to the height of the deflection
on the oscilloscope for the ____ display.
Answer: A-mode
◉ What are methods of restricting the dynamic range of the signal?
Answer: suppression, rejection, compression
◉ Most of the scan converters currently in use are of the _____ type?
Answer: digital
◉ The fraction of time that pulsed ultrasound is actually on is the
Answer: duty factor
◉ The ability of an imaging system to detect weak reflections is
called
Answer: sensitivity
◉ What image shape is produced by a linear sequenced array
transducer?
Answer: rectangular
SOLVED QUESTIONS ANSWERS ULTRASOUND
PRINCIPLES REVIEW SHEET
◉ What three things can occur when an ultrasonic beam reaches the
interface of two dissimilar materials?
Answer: reflection, refraction, mode conversion
◉ The acoustic impedance of a material is
Answer: equal to the product of density and velocity
◉ The average velocity of ultrasonic waves in soft tissue is
Answer: 1540 m/s
◉ True/False: Receiver-angle values in CW Doppler analysis do not
influence the final Doppler shift.
Answer: False
◉ Refraction occurs because of difference in ______ across an
interface between two materials
Answer: wave velocity
,◉ Reflection factor at an interface between two materials depends
primarily on the change in ______ across the interface.
Answer: acoustic impedance
◉ The velocity of sound waves is primarily dependent on
Answer: medium and mode of vibration
◉ Increasing the frequency of an ultrasonic longitudinal wave will
result in ______ in the velocity of that wave.
Answer: no change
◉ The change in direction of an ultrasonic beam, when it passes
from one medium to another, in which elasticity and density differ
from those of the first medium is called
Answer: refraction
◉ A long near zone can be obtained by
Answer: using a higher frequency transducer
◉ If a 2 MHz frequency is used in human soft tissue, the wavelength
is approximately
Answer: 0.75 mm
,◉ The ratio of particle pressure to particle velocity at a given point
within the ultrasonic field is
Answer: impedance
◉ What is the following formula used to determine?
(2 × velocity of reflector × original frequency) / velocity of sound
Answer: Doppler shift frequency
◉ The principle that states that all points on a wavefront can be
considered as point sources for the production of sperical secondary
wavelets was postulated by
Answer: Huygens
◉ A 10 dB difference in signal intensity is equivalent to a _______
difference.
Answer: tenfold
◉ The level below which signals are not transmitted through an
ultrasound receiver system is the
Answer: threshold, negative, reject level
◉ Gray-scale systems typically use _____ as a means of signal dynamic
range reduction.
, Answer: compression
◉ The strength of the echo is related to the height of the deflection
on the oscilloscope for the ____ display.
Answer: A-mode
◉ What are methods of restricting the dynamic range of the signal?
Answer: suppression, rejection, compression
◉ Most of the scan converters currently in use are of the _____ type?
Answer: digital
◉ The fraction of time that pulsed ultrasound is actually on is the
Answer: duty factor
◉ The ability of an imaging system to detect weak reflections is
called
Answer: sensitivity
◉ What image shape is produced by a linear sequenced array
transducer?
Answer: rectangular
