ARDMS SPI Exam Latest Real Exam 110 Questions
and Correct Detailed Answers | Brand New
Version 2026
EXAM OVERVIEW
The ARDMS Sonography Principles and Instrumentation (SPI) examination is a
fundamental certification for sonographers, assessing knowledge in physical principles,
instrumentation, and safety of diagnostic medical sonography. Passing the SPI
examination is a prerequisite for obtaining specialty sonography credentials offered by
ARDMS .
Key Exam Information :
• Exam Format: Computer-based, multiple-choice
• Number of Questions: 110 questions
• Time Allowed: 2 hours (120 minutes)
• Passing Score: Minimum scaled score of 555 (range 300-700)
• Cost: $250
• Testing Location: Pearson VUE testing centers
Exam Content Areas :
• Physical Principles: 15%
• Ultrasound Transducers: 16%
• Imaging Principles and Instrumentation: 28%
• Doppler Imaging Concepts: 31%
• Clinical Safety, Patient Care, and Quality Assurance: 10%
PRACTICE QUESTIONS
Question 1
When the direction of wave propagation is parallel to the particle motion of the medium,
the wave being transmitted is called a:
A) Surface wave
pg. 1
,B) Longitudinal wave
C) Transverse wave
D) Non-linear sound
Correct Answer: B
Explanation: A longitudinal wave is characterized by particle motion that is parallel to
the direction of wave propagation. Sound waves in diagnostic ultrasound are
longitudinal waves, where particles of the medium oscillate back and forth in the same
direction as the wave travels .
Question 2
If the sound beam attenuated 6 dB, what will happen to the overall intensity?
A) Quadrupled
B) Doubled
C) Halved
D) Quartered
Correct Answer: D
Explanation: Every 3 dB of attenuation halves the intensity. Therefore, 6 dB
attenuation represents two halvings, reducing the intensity to one-quarter of its original
value .
Question 3
If frequency is increased from 3 MHz to 6 MHz, what will happen to wavelength?
A) Doubled
B) Quadrupled
C) Halved
D) Quartered
Correct Answer: C
Explanation: Wavelength and frequency are inversely proportional. When frequency
doubles, wavelength is halved, assuming constant propagation speed .
Question 4
Intensity is equal to:
A) Power / Area
B) Propagation speed / Frequency
C) Density x Propagation speed
D) Area / Power
pg. 2
,Correct Answer: A
Explanation: Intensity is defined as power per unit area. It is a measure of the
concentration of energy in the sound beam .
Question 5
What is important when selecting a transducer frequency?
A) Depth
B) Power
C) Velocity
D) Propagation speed
Correct Answer: A
Explanation: The selection of transducer frequency is primarily based on the depth of
the structure being imaged. Higher frequencies provide better resolution but penetrate
less deeply .
Question 6
Frequency is a factor in:
A) Impedance
B) Tissue attenuation
C) Propagation speed
D) Tissue density
Correct Answer: B
Explanation: Attenuation (the loss of sound energy as it travels through tissue) is
frequency-dependent. Higher frequencies attenuate more rapidly than lower
frequencies .
Question 7
Which medium interface will have the greatest sound transmission?
A) Soft tissue to water
B) Organ to organ
C) Bone to organ
D) Lung to soft tissue
Correct Answer: B
Explanation: When there is a minimal mismatch in acoustic impedance between two
media (such as organ to organ), most of the sound energy is transmitted rather than
reflected .
pg. 3
, Question 8
If there is a small impedance mismatch between two mediums, what will result?
A) There will be a small reflection
B) There will be a large reflection
C) All sound will transmit
D) No sound will transmit
Correct Answer: A
Explanation: The amount of reflection depends on the difference in acoustic
impedance between two media. A small impedance mismatch results in a small
reflection .
Question 9
Which property of sound is measured in Rayls?
A) Intensity
B) Impedance
C) Density
D) Propagation speed
Correct Answer: B
Explanation: Acoustic impedance (Z) is measured in Rayls. It is the product of density
and propagation speed (Z = ρ × c) .
Question 10
If sound energy is reduced by 50%, how many decibels were lost?
A) 6 dB
B) 3 dB
C) 0 dB
D) 10 dB
Correct Answer: B
Explanation: A 3 dB reduction represents a 50% decrease in sound intensity. Decibels
are logarithmic, so 3 dB corresponds to a halving of intensity .
Question 11
To improve the quality of the motion during an electrocardiogram, which resolution
should be improved?
A) Transverse resolution
pg. 4
and Correct Detailed Answers | Brand New
Version 2026
EXAM OVERVIEW
The ARDMS Sonography Principles and Instrumentation (SPI) examination is a
fundamental certification for sonographers, assessing knowledge in physical principles,
instrumentation, and safety of diagnostic medical sonography. Passing the SPI
examination is a prerequisite for obtaining specialty sonography credentials offered by
ARDMS .
Key Exam Information :
• Exam Format: Computer-based, multiple-choice
• Number of Questions: 110 questions
• Time Allowed: 2 hours (120 minutes)
• Passing Score: Minimum scaled score of 555 (range 300-700)
• Cost: $250
• Testing Location: Pearson VUE testing centers
Exam Content Areas :
• Physical Principles: 15%
• Ultrasound Transducers: 16%
• Imaging Principles and Instrumentation: 28%
• Doppler Imaging Concepts: 31%
• Clinical Safety, Patient Care, and Quality Assurance: 10%
PRACTICE QUESTIONS
Question 1
When the direction of wave propagation is parallel to the particle motion of the medium,
the wave being transmitted is called a:
A) Surface wave
pg. 1
,B) Longitudinal wave
C) Transverse wave
D) Non-linear sound
Correct Answer: B
Explanation: A longitudinal wave is characterized by particle motion that is parallel to
the direction of wave propagation. Sound waves in diagnostic ultrasound are
longitudinal waves, where particles of the medium oscillate back and forth in the same
direction as the wave travels .
Question 2
If the sound beam attenuated 6 dB, what will happen to the overall intensity?
A) Quadrupled
B) Doubled
C) Halved
D) Quartered
Correct Answer: D
Explanation: Every 3 dB of attenuation halves the intensity. Therefore, 6 dB
attenuation represents two halvings, reducing the intensity to one-quarter of its original
value .
Question 3
If frequency is increased from 3 MHz to 6 MHz, what will happen to wavelength?
A) Doubled
B) Quadrupled
C) Halved
D) Quartered
Correct Answer: C
Explanation: Wavelength and frequency are inversely proportional. When frequency
doubles, wavelength is halved, assuming constant propagation speed .
Question 4
Intensity is equal to:
A) Power / Area
B) Propagation speed / Frequency
C) Density x Propagation speed
D) Area / Power
pg. 2
,Correct Answer: A
Explanation: Intensity is defined as power per unit area. It is a measure of the
concentration of energy in the sound beam .
Question 5
What is important when selecting a transducer frequency?
A) Depth
B) Power
C) Velocity
D) Propagation speed
Correct Answer: A
Explanation: The selection of transducer frequency is primarily based on the depth of
the structure being imaged. Higher frequencies provide better resolution but penetrate
less deeply .
Question 6
Frequency is a factor in:
A) Impedance
B) Tissue attenuation
C) Propagation speed
D) Tissue density
Correct Answer: B
Explanation: Attenuation (the loss of sound energy as it travels through tissue) is
frequency-dependent. Higher frequencies attenuate more rapidly than lower
frequencies .
Question 7
Which medium interface will have the greatest sound transmission?
A) Soft tissue to water
B) Organ to organ
C) Bone to organ
D) Lung to soft tissue
Correct Answer: B
Explanation: When there is a minimal mismatch in acoustic impedance between two
media (such as organ to organ), most of the sound energy is transmitted rather than
reflected .
pg. 3
, Question 8
If there is a small impedance mismatch between two mediums, what will result?
A) There will be a small reflection
B) There will be a large reflection
C) All sound will transmit
D) No sound will transmit
Correct Answer: A
Explanation: The amount of reflection depends on the difference in acoustic
impedance between two media. A small impedance mismatch results in a small
reflection .
Question 9
Which property of sound is measured in Rayls?
A) Intensity
B) Impedance
C) Density
D) Propagation speed
Correct Answer: B
Explanation: Acoustic impedance (Z) is measured in Rayls. It is the product of density
and propagation speed (Z = ρ × c) .
Question 10
If sound energy is reduced by 50%, how many decibels were lost?
A) 6 dB
B) 3 dB
C) 0 dB
D) 10 dB
Correct Answer: B
Explanation: A 3 dB reduction represents a 50% decrease in sound intensity. Decibels
are logarithmic, so 3 dB corresponds to a halving of intensity .
Question 11
To improve the quality of the motion during an electrocardiogram, which resolution
should be improved?
A) Transverse resolution
pg. 4
