SPI PRACTICE Questions and Answers (100%
Correct Answers) Already Graded A+
Sound waves are: [ Ans: ] longitudinal, mechanical
The speed of sound in soft tissue is closest to: [ Ans: ]
1,500 m/s
The frequency closest to the lower limit of ultrasound is: [
Ans: ] 15,000 Hz
Which is not an acoustic variable? [ Ans: ] intensity
The effects of soft tissue on ultrasound are called: [ Ans: ]
acoustic propagation properties
All of the following are true EXCEPT: [ Ans: ] two waves
with identical frequencies must interfere constructively
Put in decreasing order: deci, deca, micro, centi [ Ans: ]
deca, deci, centi micro
______________ is the time to complete one cycle [ Ans: ]
period
Which of the following sound waves is ultrasonic and least
useful? [ Ans: ] 30 KHz
What is the frequency of a wave with a 1 msec period? [
Ans: ] 1 KHz
,______________ is the distance covered by one cycle [ Ans: ]
wavelength
Which of the following is determined by the source and
the medium? [ Ans: ] range resolution
Propagation speed = ______________ x wavelength [ Ans: ]
frequency
As a result of ______________, the propagation speed
increases [ Ans: ] decreasing compressibility and density
Put in decreasing order of propagation speed: gas, liquid,
solid [ Ans: ] solid, liquid, gas
If the frequency of US is increased from 0.77 MHz to 1.54
MHz, what happens to the wavelength? [ Ans: ] halved
A sound wave's frequency is 10 MHz. The wave is
traveling in soft tissue. What is its wavelength? [ Ans: ] .15
mm
If the frequency of an US wave is doubled, what happens
to the period? [ Ans: ] halved
If the frequency of US is increased from 0.77MHz to
1.54MHz, what happens to the propagation speed? [ Ans: ]
remains the same
The units of PRF are: [ Ans: ] per minute
,The time from the beginning of a pulse until its end is
______________? [ Ans: ] pulsed duration
What happens to the speed of sound in a medium when
the bulk modulus of the medium increases? [ Ans: ] faster
___________ resolution is determined by SPL [ Ans: ] radial
or axial
If a wave's amplitude is doubled, what happens to the
power? [ Ans: ] quadrupled
Power of sound has units of: [ Ans: ] watts
If the intensity of a sound beam remains unchanged while
the beam area is reduced in half, what has happened to
the power? [ Ans: ] halved
Which of these intensities is the smallest? SATP, SPTP,
SATA [ Ans: ] SATA
The duty factor for CW ultrasound is: [ Ans: ] 1.0
What is the minimum value of the duty factor? [ Ans: ] 0%
What are the units of intensity? [ Ans: ] watts/cm2
What happens to the speed of sound in a medium when
the bulk modulus of the medium decreases? [ Ans: ]
slower
, The units of attenuation are ______; this is a ______________
scale [ Ans: ] dB, logarithmic
Sound intensity is decreased by 75%. How many decibels
of attenuation is that? [ Ans: ] 6 dB
The fundamental frequency of a transducer is 2.5 MHz.
What is the second harmonic frequency? [ Ans: ] 5 MHz
A pulse is emitted by a transducer and is traveling in soft
tissue. The go-return-time, or time-of-flight, of a sound
pulse is 130 microseconds. What is the reflector depth? [
Ans: ] 10 cm
If a 5 MHz sound wave is traveling in the tissues listed
below, which will have the longest wavelength? [ Ans: ]
bone
If a 5 MHz sound wave is traveling in the tissues listed
below, which will have the shortest wavelength? [ Ans: ]
air
What is the approximate attenuation coefficient of 1 MHz
US in soft tissue? [ Ans: ] .5 dB/cm
Rayl is the unit of: [ Ans: ] impedance
Impedance is the _________ of _________ and _________ [
Ans: ] product, propagation speed, density
What are attenuation's three components? [ Ans: ]
scattering, reflection, absorption
Correct Answers) Already Graded A+
Sound waves are: [ Ans: ] longitudinal, mechanical
The speed of sound in soft tissue is closest to: [ Ans: ]
1,500 m/s
The frequency closest to the lower limit of ultrasound is: [
Ans: ] 15,000 Hz
Which is not an acoustic variable? [ Ans: ] intensity
The effects of soft tissue on ultrasound are called: [ Ans: ]
acoustic propagation properties
All of the following are true EXCEPT: [ Ans: ] two waves
with identical frequencies must interfere constructively
Put in decreasing order: deci, deca, micro, centi [ Ans: ]
deca, deci, centi micro
______________ is the time to complete one cycle [ Ans: ]
period
Which of the following sound waves is ultrasonic and least
useful? [ Ans: ] 30 KHz
What is the frequency of a wave with a 1 msec period? [
Ans: ] 1 KHz
,______________ is the distance covered by one cycle [ Ans: ]
wavelength
Which of the following is determined by the source and
the medium? [ Ans: ] range resolution
Propagation speed = ______________ x wavelength [ Ans: ]
frequency
As a result of ______________, the propagation speed
increases [ Ans: ] decreasing compressibility and density
Put in decreasing order of propagation speed: gas, liquid,
solid [ Ans: ] solid, liquid, gas
If the frequency of US is increased from 0.77 MHz to 1.54
MHz, what happens to the wavelength? [ Ans: ] halved
A sound wave's frequency is 10 MHz. The wave is
traveling in soft tissue. What is its wavelength? [ Ans: ] .15
mm
If the frequency of an US wave is doubled, what happens
to the period? [ Ans: ] halved
If the frequency of US is increased from 0.77MHz to
1.54MHz, what happens to the propagation speed? [ Ans: ]
remains the same
The units of PRF are: [ Ans: ] per minute
,The time from the beginning of a pulse until its end is
______________? [ Ans: ] pulsed duration
What happens to the speed of sound in a medium when
the bulk modulus of the medium increases? [ Ans: ] faster
___________ resolution is determined by SPL [ Ans: ] radial
or axial
If a wave's amplitude is doubled, what happens to the
power? [ Ans: ] quadrupled
Power of sound has units of: [ Ans: ] watts
If the intensity of a sound beam remains unchanged while
the beam area is reduced in half, what has happened to
the power? [ Ans: ] halved
Which of these intensities is the smallest? SATP, SPTP,
SATA [ Ans: ] SATA
The duty factor for CW ultrasound is: [ Ans: ] 1.0
What is the minimum value of the duty factor? [ Ans: ] 0%
What are the units of intensity? [ Ans: ] watts/cm2
What happens to the speed of sound in a medium when
the bulk modulus of the medium decreases? [ Ans: ]
slower
, The units of attenuation are ______; this is a ______________
scale [ Ans: ] dB, logarithmic
Sound intensity is decreased by 75%. How many decibels
of attenuation is that? [ Ans: ] 6 dB
The fundamental frequency of a transducer is 2.5 MHz.
What is the second harmonic frequency? [ Ans: ] 5 MHz
A pulse is emitted by a transducer and is traveling in soft
tissue. The go-return-time, or time-of-flight, of a sound
pulse is 130 microseconds. What is the reflector depth? [
Ans: ] 10 cm
If a 5 MHz sound wave is traveling in the tissues listed
below, which will have the longest wavelength? [ Ans: ]
bone
If a 5 MHz sound wave is traveling in the tissues listed
below, which will have the shortest wavelength? [ Ans: ]
air
What is the approximate attenuation coefficient of 1 MHz
US in soft tissue? [ Ans: ] .5 dB/cm
Rayl is the unit of: [ Ans: ] impedance
Impedance is the _________ of _________ and _________ [
Ans: ] product, propagation speed, density
What are attenuation's three components? [ Ans: ]
scattering, reflection, absorption
