150 QUESTIONS AND CORRECT ANSWERS
BRAND NEW VERSION EXAM SCRIPT FULL
SOLUTION
⩥ 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