SPI Mock Exam Questions and Answers Plus
Rationale 2026-2027 update
1. When the ELASTICITY of a medium is HIGH, the _____ is HIGH
• A. Stiffness
• B. Propagation speed
• C. Compressibility
• D. Reflectivity
Correct Answer: C — Compressibility
Rationale: Elasticity is the ability of a medium to be compressed or deformed.
When elasticity is high, the medium is easily compressed, so compressibility is
high. Stiffness and propagation speed are inversely related to compressibility; a
highly elastic medium is less stiff and sound travels more slowly through it.
2. What term describes the number of cycles that an acoustic variable completes
in a second?
• A. Period
• B. Frequency
• C. Pulse repetition period
• D. Variable rate
Correct Answer: B — Frequency
Rationale: Frequency is the number of cycles that occur per second and is
measured in hertz (Hz). Period is the time for one cycle, PRP is the time from one
pulse to the next, and variable rate is not a standard ultrasound term.
, 3. What happens to venous flow return to the HEART when a person INHALES?
• A. Increases
• B. Decreases
• C. Remains unchanged
• D. Stops completely
Correct Answer: A — Increases
Rationale: During inhalation, the diaphragm descends and intrathoracic pressure
becomes more negative. This negative pressure draws blood into the thoracic
cavity and increases venous return to the right side of the heart.
4. What establishes the frequency of an ultrasound wave?
• A. Transducer
• B. Medium through which sound travels
• C. Both
• D. Neither
Correct Answer: A — Transducer
Rationale: Frequency is determined by the sound source, which in diagnostic
ultrasound is the transducer. The medium determines propagation speed, not
frequency.
5. Which of the following tasks is NOT performed by the receiver of an
ultrasound system?
• A. Rectification
• B. Smoothing
• C. Compression
• D. Degaussing
Rationale 2026-2027 update
1. When the ELASTICITY of a medium is HIGH, the _____ is HIGH
• A. Stiffness
• B. Propagation speed
• C. Compressibility
• D. Reflectivity
Correct Answer: C — Compressibility
Rationale: Elasticity is the ability of a medium to be compressed or deformed.
When elasticity is high, the medium is easily compressed, so compressibility is
high. Stiffness and propagation speed are inversely related to compressibility; a
highly elastic medium is less stiff and sound travels more slowly through it.
2. What term describes the number of cycles that an acoustic variable completes
in a second?
• A. Period
• B. Frequency
• C. Pulse repetition period
• D. Variable rate
Correct Answer: B — Frequency
Rationale: Frequency is the number of cycles that occur per second and is
measured in hertz (Hz). Period is the time for one cycle, PRP is the time from one
pulse to the next, and variable rate is not a standard ultrasound term.
, 3. What happens to venous flow return to the HEART when a person INHALES?
• A. Increases
• B. Decreases
• C. Remains unchanged
• D. Stops completely
Correct Answer: A — Increases
Rationale: During inhalation, the diaphragm descends and intrathoracic pressure
becomes more negative. This negative pressure draws blood into the thoracic
cavity and increases venous return to the right side of the heart.
4. What establishes the frequency of an ultrasound wave?
• A. Transducer
• B. Medium through which sound travels
• C. Both
• D. Neither
Correct Answer: A — Transducer
Rationale: Frequency is determined by the sound source, which in diagnostic
ultrasound is the transducer. The medium determines propagation speed, not
frequency.
5. Which of the following tasks is NOT performed by the receiver of an
ultrasound system?
• A. Rectification
• B. Smoothing
• C. Compression
• D. Degaussing
