SPI Physics Exam final updates!!!
2026-2027 | correct solutions with
quiz & answers | verified | highly
graded a+
True or False? Focused sound beams are considered less likely to create bioeffects
because the beams will strike fewer gas bubbles that could potentially cavitate. -
CORRECT ANSWERS-True. Small gas bubbles, or gaseous nuclei in tissues, serve as
sites of cavitation.
Certain studies of bioeffects are performed in vitro. What is the meaning of in vitro?
A) visible in a living organism
B) observations based on experiments
C) discernible in a test tube
D) perceptible in a living human being - CORRECT ANSWERS-C.
Which component of an u/s system exposes a patient to greatest risk?
A) the CRT
B) the electric cord
C) the pulser
D) the transducer - CORRECT ANSWERS-D.
T or F? The AIUM suggests that in vitro research confirming bioeffects is valuable and
valid. their results are significant and should be directly applied to the clinical arena. -
CORRECT ANSWERS-F. It is difficult to assess their direct clinical significance.
Which of the following statements regarding cavitation is true?
A) it has never been observed in any biologic media
B) stable cavitation relates to oscillating bubbles while transient relates to bursting
bubbles
C) it is a nonlethal bioeffect produced in animal experiments
D) waves with peak pressures <100MPa can never induce cavitation - CORRECT
ANSWERS-B
What is epidemiology the study of?
A) large groups
B) the prevalence of disease
C) acoustic bioeffects on the fetus - CORRECT ANSWERS-B
,T or F? One reason focused ultrasound beams with low intensities are less likely to
cause bioeffects is that a focused beam is less efficient in heating a large mass of tissue
to a critical temperature - CORRECT ANSWERS-T
Which of the following u/s beams has a characteristic that is most likely to cause
temperature elevation in soft tissue?
A) strongly focused
B) medium focused
C) unfocused - CORRECT ANSWERS-C
Research has indicated that cavitation_____.
A) never occurs
B) cannot occur with long pulses
C) can be lethal to living things
D) effects are purely theoretical - CORRECT ANSWERS-C
Which component of an u/s system is made of lead zirconate titanate (PZT)
A) matching layer
B) active element
C) damping material
D) scan converter's computer chips - CORRECT ANSWERS-B
T or F? The characteristic impedance of acoustic gel is > the matching layer's
impedance but < the piezoelectric element's impedance. - CORRECT ANSWERS-F
T or F? The piezoelectric crystal of a transducer typically has an impedance higher than
the impedance of skin. - CORRECT ANSWERS-T
Which of the following lists orders the impedance from high to low?
A) skin, gel, matching layer, PZT
B) PZT, gel matching layer, skin
C) gel, PZT, mathching layer, skin
D) PZT, matching layer, gel , skin - CORRECT ANSWERS-D
What is the thickness of the matching layer of a 2 MHz PW transducer?
A) 1.54 mm
B) 0.77 mm
C) half the wavelength of the sound wave in the PZT
D) 1/4 the wavelength of sound in the matching layer - CORRECT ANSWERS-D
An u/s pulse is traveling in soft tissue. Which of the following is most important in the
determination of the frequency of the sound?
A) the propagation speed of the matching layer
B) the thickness of the backing material
C) the impedance of the matching layer
D) the propagation speed of the active element - CORRECT ANSWERS-D
,What is the best estimate of the propagation speed of the ferroelectric element of a
transducer used in a typical diagnostic imaging lab?
A) 1.2 mm/usec
B) 4 m/sec
C) 4 mm/usec
D) 1 km/sec - CORRECT ANSWERS-C
How thick is the active element of a 3 MHz PW transducer?
A) 1.54 mm
B) 0.51 mm
C) half the wavelength of the sound wave in the PZT
D) 1/4 the wavelength of wound in the matching layer - CORRECT ANSWERS-B
T or F? The backing material helps to decrease the duty cycle at a particular PRF -
CORRECT ANSWERS-T
T or F? The backing material decreases the QF - CORRECT ANSWERS-T
T or F? The SPL is decreased with the application of backing material - CORRECT
ANSWERS-T
T or F? The PD is increased as a result of backing material - CORRECT ANSWERS-F
T or F Damping material helps to decrease the PRP at a given depth - CORRECT
ANSWERS-F
Which component of an u/s transducer is made from a slab of epoxy embedded with
tungsten particles?
A) matching layer
B) piezoelectric crystal
C) damping material
D) computer chips - CORRECT ANSWERS-C
T or F The purpose of the backing material is to shorten the pulses, thereby creating
images with better quality - CORRECT ANSWERS-T
T or F In general, imaging transducers have a lower QF and a wider BW than
therapeutic transducers - CORRECT ANSWERS-T
Which properties of the piez crystal of a CW transducer result in the high emitted
frequency?
A) thin, high prop speed
B) thick, slow speed
C) thin Slow speed
D) none of the above - CORRECT ANSWERS-D
, Which properties of the piez crystal result in highest emitted frequency?
A) thin, high speed
B) thick, slow speed
C) thin, slow speed
D) none of the aboves - CORRECT ANSWERS-A
Damping material is secured to piez material during the fabrication of a transducer.
Which of the following is not a consequence of the attachment?
A) BW increases
B) QF decreases
C) sensitivity increases
D) longer transducer case - CORRECT ANSWERS-C
For a disc-shaped PZT crystal producing continuous sound, which design will create a
beam with the shallowest focus?
A) large diameter, low frequency
B) large, high
C) small, low
D) small, high - CORRECT ANSWERS-C
1meter = _____________mm - CORRECT ANSWERS-1,000
1 cm = __________ mm - CORRECT ANSWERS-10
1 KHz = _________Hz - CORRECT ANSWERS-1,000
1 MHz = ____________ KHz - CORRECT ANSWERS-100
Arrange prefixes in order from low to high
nano-
kilo-
micro-
giga-
centi-
milli-
deca- - CORRECT ANSWERS-nano, micro, milli, centi, deca, kilo, giga
Arrange prefixes in order from high to low
centi, mega, kilo,
micro, giga, nano, deci - CORRECT ANSWERS-giga, mega, kilo, deci, centi, micro,
nano
How many cm in 3 meters? - CORRECT ANSWERS-300
How many km in 3000 meters? - CORRECT ANSWERS-3
2026-2027 | correct solutions with
quiz & answers | verified | highly
graded a+
True or False? Focused sound beams are considered less likely to create bioeffects
because the beams will strike fewer gas bubbles that could potentially cavitate. -
CORRECT ANSWERS-True. Small gas bubbles, or gaseous nuclei in tissues, serve as
sites of cavitation.
Certain studies of bioeffects are performed in vitro. What is the meaning of in vitro?
A) visible in a living organism
B) observations based on experiments
C) discernible in a test tube
D) perceptible in a living human being - CORRECT ANSWERS-C.
Which component of an u/s system exposes a patient to greatest risk?
A) the CRT
B) the electric cord
C) the pulser
D) the transducer - CORRECT ANSWERS-D.
T or F? The AIUM suggests that in vitro research confirming bioeffects is valuable and
valid. their results are significant and should be directly applied to the clinical arena. -
CORRECT ANSWERS-F. It is difficult to assess their direct clinical significance.
Which of the following statements regarding cavitation is true?
A) it has never been observed in any biologic media
B) stable cavitation relates to oscillating bubbles while transient relates to bursting
bubbles
C) it is a nonlethal bioeffect produced in animal experiments
D) waves with peak pressures <100MPa can never induce cavitation - CORRECT
ANSWERS-B
What is epidemiology the study of?
A) large groups
B) the prevalence of disease
C) acoustic bioeffects on the fetus - CORRECT ANSWERS-B
,T or F? One reason focused ultrasound beams with low intensities are less likely to
cause bioeffects is that a focused beam is less efficient in heating a large mass of tissue
to a critical temperature - CORRECT ANSWERS-T
Which of the following u/s beams has a characteristic that is most likely to cause
temperature elevation in soft tissue?
A) strongly focused
B) medium focused
C) unfocused - CORRECT ANSWERS-C
Research has indicated that cavitation_____.
A) never occurs
B) cannot occur with long pulses
C) can be lethal to living things
D) effects are purely theoretical - CORRECT ANSWERS-C
Which component of an u/s system is made of lead zirconate titanate (PZT)
A) matching layer
B) active element
C) damping material
D) scan converter's computer chips - CORRECT ANSWERS-B
T or F? The characteristic impedance of acoustic gel is > the matching layer's
impedance but < the piezoelectric element's impedance. - CORRECT ANSWERS-F
T or F? The piezoelectric crystal of a transducer typically has an impedance higher than
the impedance of skin. - CORRECT ANSWERS-T
Which of the following lists orders the impedance from high to low?
A) skin, gel, matching layer, PZT
B) PZT, gel matching layer, skin
C) gel, PZT, mathching layer, skin
D) PZT, matching layer, gel , skin - CORRECT ANSWERS-D
What is the thickness of the matching layer of a 2 MHz PW transducer?
A) 1.54 mm
B) 0.77 mm
C) half the wavelength of the sound wave in the PZT
D) 1/4 the wavelength of sound in the matching layer - CORRECT ANSWERS-D
An u/s pulse is traveling in soft tissue. Which of the following is most important in the
determination of the frequency of the sound?
A) the propagation speed of the matching layer
B) the thickness of the backing material
C) the impedance of the matching layer
D) the propagation speed of the active element - CORRECT ANSWERS-D
,What is the best estimate of the propagation speed of the ferroelectric element of a
transducer used in a typical diagnostic imaging lab?
A) 1.2 mm/usec
B) 4 m/sec
C) 4 mm/usec
D) 1 km/sec - CORRECT ANSWERS-C
How thick is the active element of a 3 MHz PW transducer?
A) 1.54 mm
B) 0.51 mm
C) half the wavelength of the sound wave in the PZT
D) 1/4 the wavelength of wound in the matching layer - CORRECT ANSWERS-B
T or F? The backing material helps to decrease the duty cycle at a particular PRF -
CORRECT ANSWERS-T
T or F? The backing material decreases the QF - CORRECT ANSWERS-T
T or F? The SPL is decreased with the application of backing material - CORRECT
ANSWERS-T
T or F? The PD is increased as a result of backing material - CORRECT ANSWERS-F
T or F Damping material helps to decrease the PRP at a given depth - CORRECT
ANSWERS-F
Which component of an u/s transducer is made from a slab of epoxy embedded with
tungsten particles?
A) matching layer
B) piezoelectric crystal
C) damping material
D) computer chips - CORRECT ANSWERS-C
T or F The purpose of the backing material is to shorten the pulses, thereby creating
images with better quality - CORRECT ANSWERS-T
T or F In general, imaging transducers have a lower QF and a wider BW than
therapeutic transducers - CORRECT ANSWERS-T
Which properties of the piez crystal of a CW transducer result in the high emitted
frequency?
A) thin, high prop speed
B) thick, slow speed
C) thin Slow speed
D) none of the above - CORRECT ANSWERS-D
, Which properties of the piez crystal result in highest emitted frequency?
A) thin, high speed
B) thick, slow speed
C) thin, slow speed
D) none of the aboves - CORRECT ANSWERS-A
Damping material is secured to piez material during the fabrication of a transducer.
Which of the following is not a consequence of the attachment?
A) BW increases
B) QF decreases
C) sensitivity increases
D) longer transducer case - CORRECT ANSWERS-C
For a disc-shaped PZT crystal producing continuous sound, which design will create a
beam with the shallowest focus?
A) large diameter, low frequency
B) large, high
C) small, low
D) small, high - CORRECT ANSWERS-C
1meter = _____________mm - CORRECT ANSWERS-1,000
1 cm = __________ mm - CORRECT ANSWERS-10
1 KHz = _________Hz - CORRECT ANSWERS-1,000
1 MHz = ____________ KHz - CORRECT ANSWERS-100
Arrange prefixes in order from low to high
nano-
kilo-
micro-
giga-
centi-
milli-
deca- - CORRECT ANSWERS-nano, micro, milli, centi, deca, kilo, giga
Arrange prefixes in order from high to low
centi, mega, kilo,
micro, giga, nano, deci - CORRECT ANSWERS-giga, mega, kilo, deci, centi, micro,
nano
How many cm in 3 meters? - CORRECT ANSWERS-300
How many km in 3000 meters? - CORRECT ANSWERS-3
