ARDMS SPI EXAM LATEST REAL EXAM 200+
QUESTIONS AND CORRECT ANSWERS|AGRADE
List all these metric terms in increasing order:
A. mega
B. micro
C. milli
D. hecto
E. deca
F. deci - ANSWER>> micro, milli, deci, deca, hecto, mega
List all these metric terms in decreasing order:
A. nano
B. canti
C. giga
D. kilo
E. hecto
F. micro - ANSWER>> giga, kilo,hecto, centi, micro, nano
Sound pulses travel through biologic tissue, or . - ANSWER>> Media
All waves carry from one location to another. - ANSWER>> Energy
Sound is a wave in which particles in the medium move. - ANSWER>>
Mechanical
Sound cannot travel through a ; it must travel through a . - ANSWER>>
Vacuum, medium
What does compressed mean? - ANSWER>> Squeezed together
What does rarefied mean? - ANSWER>> Stretched apart
Sound travels in a line. - ANSWER>> Straight
Sound waves are waves. - ANSWER>> Longitudinal
What is the propagation speed dependent on? - ANSWER>> The medium
Are there any biologic effects on tissue? - ANSWER>> No
,Sound waves are identified by - ANSWER>> Oscillations in acoustic variables
What are the three acoustic variables? (With their units) - ANSWER>> pressure -
pascals (Pa), density - kg/cm^3, distance - cm, mm
If something other than pressure, density, or distance (particle motion) rhythmically
oscillates in a wave, then the wave... - ANSWER>> Is not a sound wave
Sound waves are also known as - ANSWER>> Acoustic waves
What are the seven Acoustic Parameters? - ANSWER>> Period, frequency, amplitude,
power, intensity, wavelength, propagation speed
Particles move in a direction that is perpendicular to the direction that the wave
propagates in what wave? - ANSWER>> Transverse wave
Particles move in the same direction that the wave propagates in a
wave. - ANSWER>> Longitudinal
When are a pair of waves considered in-phase? - ANSWER>> When their peaks and
troughs occur at the same time and at the same location
Considered "in step"
What happens when two waves are out-of-phase? - ANSWER>> Their peaks occur at
different times, and so do their troughs
"out of step"
What is interference? - ANSWER>> When more than one beam travels in a medium
and arrive at the same location at exactly the same time
These waves lose their individual characteristics and combine to form a single wave
The interference of in-phase waves results in a single wave of amplitude.
This is called . - ANSWER>> Greater, constructive interference
(Larger Wave)
The interference of a pair of out-of-phase waves results in the formation of a single
wave of amplitude. This combination is called .-
ANSWER>> Lesser, destructive interference
(Smaller Wave)
When frequencies of waves differ, what kind of wave occurs? - ANSWER>> Both
constructive and destructive interference
What do waves transfer from one location to another? - ANSWER>> Energy
Two waves are traveling in a medium and arrive at a location at the same time. What
event takes place? - ANSWER>> Interference
Which types of waves will exhibit both constructive and destructive interference? -
ANSWER>> Waves of different frequency
,What units are used to report the pressure of a sound beam? - ANSWER>> Pascals,
Pa
What describes features of a sound wave? - ANSWER>> Parameters
What is the source of a sound wave? - ANSWER>> The ultrasound system and the
transducer
Some parameters are determined by the tissue through which the sound is traveling,
also called a . - ANSWER>> Medium
What is period? And what is it determined by? - ANSWER>> The time it takes a wave to
vibrate a single cycle, or the time from start of a cycle to the start of the next cycle
It is determined by the source
What is frequency? And what is it determined by? - ANSWER>> The number of cycles
that occurs in one second
Determined by the sound source only
1 cycle/second = - ANSWER>> 1 Hertz
If the frequency of a sound wave is less than , it is below the threshold of human
hearing and cannot be heard. These are defined as . - ANSWER>> 20
Hz, infrasonic
Audible sound waves that humans can hear are frequencies between
. - ANSWER>> 20 Hz and 20,000 Hz
What is ultrasound's frequency? - ANSWER>> Greater than 20,000 Hz or 20 kHz
Why is frequency important in diagnostic sonography? - ANSWER>> It affects
penetration and image quality
Period and frequency are related to each other. - ANSWER>> Inversely
When two reciprocal parameters are multiplied together, the result is: - ANSWER>> 1
What three parameters describe the size, or magnitude, or strength of a sound wave? -
ANSWER>> Amplitude, power, intensity
What is Amplitude? - ANSWER>> The "bigness" of a wave. It is the difference between
the maximum value and the average or undisturbed value of an acoustic variable
Also the difference between the minimum value and the average value of the acoustic
variable
What is Amplitude determined by? And is it adjustable? - ANSWER>> Initially,
amplitude is determined only by the sound source, however amplitude decreases as
sound propagates through the body (attenuation)
Yes, a control on ultrasound systems allows the sonographer to alter initial amplitude
, What is the difference between amplitude and peak-to-peak amplitude? - ANSWER>>
Amplitude is measured from the middle value to the maximum value. Peak-to-peak
amplitude is the difference between maximum and minimum values of an acoustic
variable
Peak-to-peak is twice the value of the amplitude
What is power? - ANSWER>> The rate of energy transfer or the rate at which work is
performed. Power, like amplitude, describes the "bigness" of the wave
What is power determined by? And can it be changed? - ANSWER>> Determined by
the sound source only
It CAN be changed
How are amplitude and power related? - ANSWER>> Both describe the size, or
magnitude of a wave. When power increases, so does amplitude
Power is proportional to... - ANSWER>> amplitude^2
What is intensity? - ANSWER>> The concentration of energy in a sound beam Intensity
= Power/area
What is intensity determined by? And is it adjustable? - ANSWER>> Sound Source
Yes, it is adjustable
How is intensity related to power and amplitude? - ANSWER>> Intensity is proportional
to power
Intensity is proportional to amplitude^2
What is the distance or length of one complete cycle called? - ANSWER>> Wavelength
What is wavelength determined by? And is it adjustable? - ANSWER>> Both the
medium and source
No, it is not adjustable
What is the relationship between wavelength and frequency? - ANSWER>> As long as
a wave remains in one medium, wavelength and frequency are inversely related
As frequency increases, wavelength decreases. The lower the frequency, the longer the
wavelength
What is the wavelength of 1 MHz sound in soft tissue? - ANSWER>> 1.54 mm
What is the wavelength of other frequency sound waves in soft tissue? - ANSWER>>
Sound with a frequency of 2 MHz has a wavelength of 0.77 mm in soft tissue. 1.54mm/2
= 0.77 mm
What is the wavelength equation? - ANSWER>> wavelength =
(1.54mm/μsec)/(frequency)
