Which of the following characteristics will create the slowest speed of sound?
a. high density, high stiffness
b. low density, high stiffness
c. high density, low stiffness
d. low density, low stiffness - CORRECT ANSWER-c
If the power in a beam is 1 watt and the area is 5 cm^2, what is the beam's intensity?
a. 5 W/cm^2
b. 1 W/cm^2
c. 0.2 W/cm^2
d. 1 watt - CORRECT ANSWER-c
If intensity remains the same while the power is doubled, what has happened to the
beam area?
a. quadrupled
b. doubled
c. halved
d. unchanged - CORRECT ANSWER-b
Variation in all of the following identify specific waves as acoustic waves except:
a. pressure
b. parameters
c. density
d. acoustic variables - CORRECT ANSWER-b
All of the following are true of sound waves except:
a. they are acoustic
b. they are pressure waves
c. they are transverse
d. they move energy - CORRECT ANSWER-c
All of the following are acoustic parameters except:
a. pressure
b. period
c. propagation speed
d. frequency - CORRECT ANSWER-a
Which of the following best describes sound waves?
a. transverse, pressure waves
b. transverse, longitudinal waves
,c. longitudinal, out-of-phase waves
d. longitudinal, pressure waves - CORRECT ANSWER-d
What do waves transfer from one location to another?
a. matter
b. molecules
c. energy
d. water - CORRECT ANSWER-C
Which of the following best describes sound waves?
a. a series of compressions and rarefactions
b. waves that are heard by man
c. movement if molecules and energy from one location to another
d. waves that are used to make images of anatomy - CORRECT ANSWER-a
Which of the following terms does not belong with the others?
a. compression
b. region of high density
c. region of high pressure
d. wide molecular spacing - CORRECT ANSWER-d
Two waves are traveling in a medium and arrive at a location at the same time. What
event takes place?
a. constructive interference
b. destructive interference
c. interference
d. reflection - CORRECT ANSWER-c
Which types of waves will exhibit both constructive and destructive interference?
a. waves of different amplitudes
b. a pair of longitudinal waves
c. waves of different frequencies
d. out-of-phase waves - CORRECT ANSWER-c
What units are used to report the pressure of a sound beam?
a. pounds
b. centimeters
c. pascals
d. kg/cm - CORRECT ANSWER-c
T/F Acoustic variables allow us to determine which waves are sound waves and which
are not. - CORRECT ANSWER-t
,T/F Acoustic parameters are used to describe the features of sound waves - CORRECT
ANSWER-t
Which of the following waves is infrasonic?
a. 4MHz
b. 400 kHz
c. 28 Hz
d. 2 Hz - CORRECT ANSWER-d
Identify the wave that is ultrasonic.
a. 400 mHz
b. 4 MHz
c. 28 Hz
d. 2 Hz - CORRECT ANSWER-b
Which of these waves is ultrasonic and most useful in diagnostic sonography?
a. 400 MHz
b. 4 MHz
c. 2 kHz
d. 200,000 Hz - CORRECT ANSWER-b
Identify all the waves that are inaudible (more than 1 answer may be correct)
a. 4 MHz
b. 400 kHz
c. 28 Hz
d. 2 Hz - CORRECT ANSWER-a, b, d
Which of the following waves has the longest period?
a. 2 MHz
b. 4,000 Hz
c. 6 Hz
d. 1 kHz - CORRECT ANSWER-c
Of the four waves whose periods are listed below, which has the highest frequency?
a. 8 s
b. 80 µs
c. 8 Ms
d. 800 ks - CORRECT ANSWER-b
Of the four waves whose frequencies are listed below, which has the shortest period?
a. 12 kHz
b. 6,000 Hz
c. 205 Hz
d. 1 kHz - CORRECT ANSWER-a
Of the four waves whose periods are listed below, which has the lowest frequency?
, a. 8 s
b. 80 µs
c. 8 Ms
d. 800 ks - CORRECT ANSWER-c
T/F A wave with a frequency if 15,000 MHz is ultrasonic. - CORRECT ANSWER-t
T/F If the amplitude of a wave is increased to 3 times its original value, the intensity is
increased by 6 times. - CORRECT ANSWER-f
T/F If the power of a wave is halved, the intensity is reduced to one-fourth of its original
value. - CORRECT ANSWER-f
T/F Propagation speed increases as frequency increases. - CORRECT ANSWER-f
Medium 1 has a density of 9 and a stiffness of 6. Medium 2 has a density of 8 and a
stiffness of 6. In which medium will sound travel slower?
a. Medium 1
b. Medium 2 - CORRECT ANSWER-a
Which of the following characteristics will create the fastest speed of sound?
a. high density, high stiffness
b. low density, high stiffness
c. high density, low stiffness
d. low density, low stiffness - CORRECT ANSWER-b
A sound beam travels a total of 10 cm in 2 seconds. What is the speed of the sound?
a. 10 cm/sec
b. 2 cm/sec
c. 5 cm/sec
d. 0.2 cm/sec - CORRECT ANSWER-c
T/F Propagation speed increases as frequency decreases. - CORRECT ANSWER-f
T/F Propagation speed does not change as frequency increases. - CORRECT
ANSWER-t
What is the wavelength of 3 MHz sound in soft tissue?
a. 0.51 m
b. 0.51 km
c. 0.51 mm
d. 0.51 nm
e. 0.51 µm - CORRECT ANSWER-c
What is the wavelength of a wave with an unknown frequency traveling in soft tissue?