DMS 100 Exam 2 2026 – Introduction to Diagnostic Medical Sonography
Fundamentals Study Guide
frequency - correct answer ✔✔ # of sound waves per second
MHz - correct answer ✔✔ frequency for dms is measured in _____.
2-15 MHz - correct answer ✔✔ Frequency range for Diagnostic medical ultrasound
medium - correct answer ✔✔ sound waves require a ______ to travel in
the piezoelectric effect - correct answer ✔✔ Vibration created by electrical energy of the
piezoelectric crystal (as the top of the transducer) generates a sound wave
Pulse echo principle - correct answer ✔✔ ultrasound imaging in which pulses are reflected and
used to produce a display
wavelength - correct answer ✔✔ length/distance between a single cycle
higher - correct answer ✔✔ higher frequency = _____ resolution
1540 cm/s - correct answer ✔✔ average speed of sound in all mediums
stiffness; density - correct answer ✔✔ speed changes based on _______ & _________.
faster - correct answer ✔✔ stiffer tissue = ______ sound waves
, slower - correct answer ✔✔ high density = ______ sound waves
air; bone - correct answer ✔✔ sound waves are slowest in ______ & fastest in ______.
Absorption
Scatter
Reflection
Refraction - correct answer ✔✔ 4 things that happen to sound waves in the body
absorption - correct answer ✔✔ conversion of acoustic energy into heat (reduces sound energy)
50 - correct answer ✔✔ no bio effects noted for exposure durations up to _____ hours
scatter - correct answer ✔✔ the transfer of acoustic energy
degrades image quality
no benefit to image - correct answer ✔✔ why is scatter bad
relfection - correct answer ✔✔ the process of sending back acoustic energy incident on a tissue
interference
high impedance - correct answer ✔✔ why does air and bone completely reflect sound waves?
different - correct answer ✔✔ When acoustic impedance of two tissue types is __________, the
reflection is going to be very strong
white - correct answer ✔✔ strong reflections = ____ dots.
Fundamentals Study Guide
frequency - correct answer ✔✔ # of sound waves per second
MHz - correct answer ✔✔ frequency for dms is measured in _____.
2-15 MHz - correct answer ✔✔ Frequency range for Diagnostic medical ultrasound
medium - correct answer ✔✔ sound waves require a ______ to travel in
the piezoelectric effect - correct answer ✔✔ Vibration created by electrical energy of the
piezoelectric crystal (as the top of the transducer) generates a sound wave
Pulse echo principle - correct answer ✔✔ ultrasound imaging in which pulses are reflected and
used to produce a display
wavelength - correct answer ✔✔ length/distance between a single cycle
higher - correct answer ✔✔ higher frequency = _____ resolution
1540 cm/s - correct answer ✔✔ average speed of sound in all mediums
stiffness; density - correct answer ✔✔ speed changes based on _______ & _________.
faster - correct answer ✔✔ stiffer tissue = ______ sound waves
, slower - correct answer ✔✔ high density = ______ sound waves
air; bone - correct answer ✔✔ sound waves are slowest in ______ & fastest in ______.
Absorption
Scatter
Reflection
Refraction - correct answer ✔✔ 4 things that happen to sound waves in the body
absorption - correct answer ✔✔ conversion of acoustic energy into heat (reduces sound energy)
50 - correct answer ✔✔ no bio effects noted for exposure durations up to _____ hours
scatter - correct answer ✔✔ the transfer of acoustic energy
degrades image quality
no benefit to image - correct answer ✔✔ why is scatter bad
relfection - correct answer ✔✔ the process of sending back acoustic energy incident on a tissue
interference
high impedance - correct answer ✔✔ why does air and bone completely reflect sound waves?
different - correct answer ✔✔ When acoustic impedance of two tissue types is __________, the
reflection is going to be very strong
white - correct answer ✔✔ strong reflections = ____ dots.
