SPI Examination Review for Ultrasound 2026 – Sonography Physics and Imaging
Principles Study Guide
What type of wave is sound?
A. mechanical, transverse
B. mechanical, longitudinal
C. transverse, longitudinal
D. lateral wave - correct answer ✔✔ B) mechanical, longitudinal
The frequency ranges for ultrasound are:
A. <20 Hz
B. 20 to 20,000 Hz
C. >20kHz
D. >2000 HZ - correct answer ✔✔ C) ultrasound is defined as sound with a frequency >20,000
Hz (20kHz)
The speed of sound in soft tissue is:
A. 1.54 mm/s
B. 1540 m/s
C. 1540 km/s
D. 1.54 m/μs - correct answer ✔✔ B) sound travels through soft tissue at 1540 m/s
Which of the following transducers fires the elements in groups?
A. Linear sequenced array
B. Phased array
C. Mechanical sector
,D. Linear phased array - correct answer ✔✔ A) The linear sequenced array fires the elements in
groups
The unit for wavelength is:
A. Millimeters
B. Hertz
C. Microseconds
D. Milliliters - correct answer ✔✔ A) Wavelength is a distance, therefore the unit must be a unit
of distance such as millimeters
Enhancement is caused by:
A. Strongly reflecting structures
B. Propagation speed errors
C. Snell's law
D. Weakly attenuation structures - correct answer ✔✔ D) Enhancement occurs when sound
passes through a weakly attenuating structure, such as a cyst
The wavelength in a material having a propagation speed of 1.5 mm/μs employing a transducer
frequency of 5.0 MHM is:
A. 0.3 mm
B. 0.3 cm
C. 0.6 mm
D. 3.0 mm - correct answer ✔✔ A) Wavelength = c/f therefore, 1.5 mm/μs divided by 5MHZ =
0.3 mm
An ultrasound transducer converts:
A. Electrical energy into light and heat
B. Electrical energy into mechanical energy
, C. Mechanical energy into radiation
D. Sound into ultrasound - correct answer ✔✔ B) Ultrasound transducers convert mechanical
energy into electrical energy and vice versa
Arrange the following media in the correct order from the lowest ATTENUATION to highest.
A. Air, Fat, Muscle, Bone
B. Muscle, Fat, Air, Bone
C. Fat, Muscle, Bone, Air
D. Muscle, Air, Fat, Bone - correct answer ✔✔ C) Fat, Muscle, Bone, Air
Air is the highest attenuator of ultrasound
Arrange the following media in terms of PROPAGATION SPEED, from lowest to highest.
A. Air, Fat, Muscle, Bone
B. Muscle, Fat, Air, Bone
C. Bone, Muscle, Fat, Air
D. Muscle, Air, Fat, Bone - correct answer ✔✔ A) Air, Fat, Muscle, Bone
Note** that this order is for PROPAGATION SPEED, not for attenuation. Air has the slowest
propagation speed and bone has the highest
If the frequency doubles, what happens to the wavelength?
A. Increases fourfold
B. Increases twofold
C. Decreases by one half
D. Frequency has no relationship to wavelength - correct answer ✔✔ C) Frequency and
wavelength are inversely related
Principles Study Guide
What type of wave is sound?
A. mechanical, transverse
B. mechanical, longitudinal
C. transverse, longitudinal
D. lateral wave - correct answer ✔✔ B) mechanical, longitudinal
The frequency ranges for ultrasound are:
A. <20 Hz
B. 20 to 20,000 Hz
C. >20kHz
D. >2000 HZ - correct answer ✔✔ C) ultrasound is defined as sound with a frequency >20,000
Hz (20kHz)
The speed of sound in soft tissue is:
A. 1.54 mm/s
B. 1540 m/s
C. 1540 km/s
D. 1.54 m/μs - correct answer ✔✔ B) sound travels through soft tissue at 1540 m/s
Which of the following transducers fires the elements in groups?
A. Linear sequenced array
B. Phased array
C. Mechanical sector
,D. Linear phased array - correct answer ✔✔ A) The linear sequenced array fires the elements in
groups
The unit for wavelength is:
A. Millimeters
B. Hertz
C. Microseconds
D. Milliliters - correct answer ✔✔ A) Wavelength is a distance, therefore the unit must be a unit
of distance such as millimeters
Enhancement is caused by:
A. Strongly reflecting structures
B. Propagation speed errors
C. Snell's law
D. Weakly attenuation structures - correct answer ✔✔ D) Enhancement occurs when sound
passes through a weakly attenuating structure, such as a cyst
The wavelength in a material having a propagation speed of 1.5 mm/μs employing a transducer
frequency of 5.0 MHM is:
A. 0.3 mm
B. 0.3 cm
C. 0.6 mm
D. 3.0 mm - correct answer ✔✔ A) Wavelength = c/f therefore, 1.5 mm/μs divided by 5MHZ =
0.3 mm
An ultrasound transducer converts:
A. Electrical energy into light and heat
B. Electrical energy into mechanical energy
, C. Mechanical energy into radiation
D. Sound into ultrasound - correct answer ✔✔ B) Ultrasound transducers convert mechanical
energy into electrical energy and vice versa
Arrange the following media in the correct order from the lowest ATTENUATION to highest.
A. Air, Fat, Muscle, Bone
B. Muscle, Fat, Air, Bone
C. Fat, Muscle, Bone, Air
D. Muscle, Air, Fat, Bone - correct answer ✔✔ C) Fat, Muscle, Bone, Air
Air is the highest attenuator of ultrasound
Arrange the following media in terms of PROPAGATION SPEED, from lowest to highest.
A. Air, Fat, Muscle, Bone
B. Muscle, Fat, Air, Bone
C. Bone, Muscle, Fat, Air
D. Muscle, Air, Fat, Bone - correct answer ✔✔ A) Air, Fat, Muscle, Bone
Note** that this order is for PROPAGATION SPEED, not for attenuation. Air has the slowest
propagation speed and bone has the highest
If the frequency doubles, what happens to the wavelength?
A. Increases fourfold
B. Increases twofold
C. Decreases by one half
D. Frequency has no relationship to wavelength - correct answer ✔✔ C) Frequency and
wavelength are inversely related
