DAVIES SPI: II. PHYSICAL PRINCIPLES
(20% OF ARDMS) EXAM QUESTIONS
WITH 100% CORRECT ANSWERS
LATEST VERSION 2025/2026.
You have increased the transmit power while performing a pelvic ultrasound examination. This
action increases which of the following?
A. Penetration
B. Acoustic power
C. Image brightness
D. Voltage applied to the transducer elements
E. All of the above - ANS E. All of the above
Attenuation of the sound beam increases with increasing:
A. Path length
B. Absorption
C. Frequency
D. Scattering and reflection
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,E. All of the above - ANS E. All of the above
<The attenuation coefficient is the degree of attenuation for each centimeter of sound
propagation. Anything that increases attenuation will increase the attenuation coefficient>
Which prefix equals 10^(-3)?
A. Micro
B. Milli
C. Mega
D. Centi
E. None of the above - ANS B. Milli
<Micro is 10^(-6), mega is 10^6, and centi is 10^(-2)>
You are imaging with a 5 MHz linear array transducer. What sound parameter stays constant as
the beam propagates through the tissue?
A. Frequency
B. Intensity
C. Amplitude
D. Wavelength
E. None of the above - ANS E. None of the above
<As sound propagates through tissue, high frequencies are attenuated more rapidly than low
frequencies. This results in a shifting toward the lower frequencies in the transmitted
bandwidth with increasing depth. The intensity and amplitude of the beam decrease as a result
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,of attenuation. The wavelength is altered with the downshifting of the overall frequency
bandwidth>
The time that it takes for one pulse to occur is known as the:
A. Duty factor
B. Spatial pulse length
C. Wavelength
D. Pulse repetition frequency
E. Pulse duration - ANS E. Pulse duration
Which statement about the two pulse trains displayed below is true? Each represents a signal vs
time.
A. A has a lower frequency than B
B. B has a longer period than A
C. A has a shorter wavelength than B
D. A has a better axial resolution than B
E. A has a shorter spatial pulse length than B
Image A: radio waves
Image B: gamma rays - ANS A. A has a lower frequency than B
<Period is the time it takes one complete cycle to occur. A's period is longer than B's. The pulse
train with the shortest wavelength would have the highest frequency, which again is B. The
shortest pulse (B) will produce the better axial resolution. The longest pulse (A) produces the
greatest spatial pulse length>
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, In order to display a structure on your sonographic image the sound beam must be reflected at
the interface. What is required for sound reflection at the interface of two structures?
A. Oblique incidence at the interface boundary
B. Temperature differences between the two media
C. A difference in the acoustic impedance of the media
D. Different media diameters
E. Different attenuation coefficients - ANS C. A difference in the acoustic impedance of the
media
You notice that the image in the far field is less bright compared to the near field. This is due to:
A. Sound attenuation
B. Propagation speed variation
C. Refraction
D. Diffraction
E. The Doppler effect - ANS A. Sound attenuation
<As sound propagates through tissue, the beam strength is weakened through absorption,
reflection, and other interactions with the medium. This weakening of beam strength is termed
attenuation and accounts for decreased brightness of the image in the far filed compared to the
near field>
What interaction of ultrasound and tissue is primarily responsible for imaging the internal
structure of organs?
A. Specular reflection
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
(20% OF ARDMS) EXAM QUESTIONS
WITH 100% CORRECT ANSWERS
LATEST VERSION 2025/2026.
You have increased the transmit power while performing a pelvic ultrasound examination. This
action increases which of the following?
A. Penetration
B. Acoustic power
C. Image brightness
D. Voltage applied to the transducer elements
E. All of the above - ANS E. All of the above
Attenuation of the sound beam increases with increasing:
A. Path length
B. Absorption
C. Frequency
D. Scattering and reflection
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,E. All of the above - ANS E. All of the above
<The attenuation coefficient is the degree of attenuation for each centimeter of sound
propagation. Anything that increases attenuation will increase the attenuation coefficient>
Which prefix equals 10^(-3)?
A. Micro
B. Milli
C. Mega
D. Centi
E. None of the above - ANS B. Milli
<Micro is 10^(-6), mega is 10^6, and centi is 10^(-2)>
You are imaging with a 5 MHz linear array transducer. What sound parameter stays constant as
the beam propagates through the tissue?
A. Frequency
B. Intensity
C. Amplitude
D. Wavelength
E. None of the above - ANS E. None of the above
<As sound propagates through tissue, high frequencies are attenuated more rapidly than low
frequencies. This results in a shifting toward the lower frequencies in the transmitted
bandwidth with increasing depth. The intensity and amplitude of the beam decrease as a result
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,of attenuation. The wavelength is altered with the downshifting of the overall frequency
bandwidth>
The time that it takes for one pulse to occur is known as the:
A. Duty factor
B. Spatial pulse length
C. Wavelength
D. Pulse repetition frequency
E. Pulse duration - ANS E. Pulse duration
Which statement about the two pulse trains displayed below is true? Each represents a signal vs
time.
A. A has a lower frequency than B
B. B has a longer period than A
C. A has a shorter wavelength than B
D. A has a better axial resolution than B
E. A has a shorter spatial pulse length than B
Image A: radio waves
Image B: gamma rays - ANS A. A has a lower frequency than B
<Period is the time it takes one complete cycle to occur. A's period is longer than B's. The pulse
train with the shortest wavelength would have the highest frequency, which again is B. The
shortest pulse (B) will produce the better axial resolution. The longest pulse (A) produces the
greatest spatial pulse length>
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, In order to display a structure on your sonographic image the sound beam must be reflected at
the interface. What is required for sound reflection at the interface of two structures?
A. Oblique incidence at the interface boundary
B. Temperature differences between the two media
C. A difference in the acoustic impedance of the media
D. Different media diameters
E. Different attenuation coefficients - ANS C. A difference in the acoustic impedance of the
media
You notice that the image in the far field is less bright compared to the near field. This is due to:
A. Sound attenuation
B. Propagation speed variation
C. Refraction
D. Diffraction
E. The Doppler effect - ANS A. Sound attenuation
<As sound propagates through tissue, the beam strength is weakened through absorption,
reflection, and other interactions with the medium. This weakening of beam strength is termed
attenuation and accounts for decreased brightness of the image in the far filed compared to the
near field>
What interaction of ultrasound and tissue is primarily responsible for imaging the internal
structure of organs?
A. Specular reflection
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
