DMS 150 Final Exam Review 2026 – Diagnostic Medical Sonography
Fundamentals and Imaging Study Guide
The ___ is a shift in frequency caused by relative motion between the observer & target. -
correct answer ✔✔ Doppler effect
A *positive shift* is caused by motion _________ the observer. - correct answer ✔✔ towards
A _________ shift is caused by motion *away* from the observer. - correct answer ✔✔ negative
A Doppler shift will __________ if both the target & observer are moving *away* from each
other. - correct answer ✔✔ increase
A Doppler shift will ________ if both the target and observer are moving *towards* each other.
- correct answer ✔✔ increase
A Doppler shift will _____ if both the target & observer are moving in the *same direction*. -
correct answer ✔✔ decrease
The _____ the target moves, the higher the Doppler shift. - correct answer ✔✔ faster
The Doppler shifted frequency is _______ to the target velocity. - correct answer ✔✔
proportional
The Doppler shifted frequency is _____ to the operating frequency. - correct answer ✔✔
proportional
, The Doppler shifted frequency is _____ to the propagation velocity. - correct answer ✔✔
inversely proportional
Doppler shift equation - correct answer ✔✔ 2vf cos/ c
What are the 6 functions an ultrasound machine must perform? - correct answer ✔✔ 1.
transmit beam
2. receive beam
3. process the returned data
4. perform measurements
5. display the processed data
6. store the processed data
Transmit power - correct answer ✔✔ controls the amplitude of the excitation voltage which
drives the transducer crystals
Dynamic range - correct answer ✔✔ the *ratio of the largest to the smallest signal* strength
that each component processes
maximum : minimum amplitude = - correct answer ✔✔ dynamic range
signal - correct answer ✔✔ reflections from the tissue that are converted into images
Noise - correct answer ✔✔ any unwanted signal; random white speckle
Noise floor - correct answer ✔✔ The amplitude level *below* which no signals are visible
because of the presence of noise
Fundamentals and Imaging Study Guide
The ___ is a shift in frequency caused by relative motion between the observer & target. -
correct answer ✔✔ Doppler effect
A *positive shift* is caused by motion _________ the observer. - correct answer ✔✔ towards
A _________ shift is caused by motion *away* from the observer. - correct answer ✔✔ negative
A Doppler shift will __________ if both the target & observer are moving *away* from each
other. - correct answer ✔✔ increase
A Doppler shift will ________ if both the target and observer are moving *towards* each other.
- correct answer ✔✔ increase
A Doppler shift will _____ if both the target & observer are moving in the *same direction*. -
correct answer ✔✔ decrease
The _____ the target moves, the higher the Doppler shift. - correct answer ✔✔ faster
The Doppler shifted frequency is _______ to the target velocity. - correct answer ✔✔
proportional
The Doppler shifted frequency is _____ to the operating frequency. - correct answer ✔✔
proportional
, The Doppler shifted frequency is _____ to the propagation velocity. - correct answer ✔✔
inversely proportional
Doppler shift equation - correct answer ✔✔ 2vf cos/ c
What are the 6 functions an ultrasound machine must perform? - correct answer ✔✔ 1.
transmit beam
2. receive beam
3. process the returned data
4. perform measurements
5. display the processed data
6. store the processed data
Transmit power - correct answer ✔✔ controls the amplitude of the excitation voltage which
drives the transducer crystals
Dynamic range - correct answer ✔✔ the *ratio of the largest to the smallest signal* strength
that each component processes
maximum : minimum amplitude = - correct answer ✔✔ dynamic range
signal - correct answer ✔✔ reflections from the tissue that are converted into images
Noise - correct answer ✔✔ any unwanted signal; random white speckle
Noise floor - correct answer ✔✔ The amplitude level *below* which no signals are visible
because of the presence of noise
