Propagation Speed Flashcards
An ultrasound pulse propagates from soft tissue through a mass. Sound’s propagation speed in the mass is 1,575 m/s.
True or False?
The frequency of the wave increases as it travels through the mass.
False
An ultrasound pulse propagates from soft tissue through a mass. Sound’s propagation speed in the mass is 1,575 m/s.
True or False?
The period of the sound wave decreases as it travels through the mass.
False
An ultrasound pulse propagates from soft tissue through a mass. Sound’s propagation speed in the mass is 1,575 m/s.
True or False?
The wavelength increases while the wave travels through the mass.
True
An ultrasound pulse propagates from soft tissue through a mass. Sound’s propagation speed in the mass is 1,575 m/s.
True or False?
The power in the wave increases as it travels through the mass.
False
Three sound waves with identical frequencies of 3 MHz have powers of 2 mW, 5 mW, and 15 mW. They all travel through three media–wood, brick, and fat–with identical thicknesses of 5 cm.
True or False?
The waves travel through all three media at the same speed since they have identical frequencies.
False
Three sound waves with identical frequencies of 3 MHz have powers of 2 mW, 5 mW, and 15 mW. They all travel through three media–wood, brick, and fat–with identical thicknesses of 5 cm.
True or False?
The sound waves travel through all three media at different speeds because the waves have different powers.
False
Three sound waves with identical frequencies of 3 MHz have powers of 2 mW, 5 mW, and 15 mW. They all travel through three media–wood, brick, and fat–with identical thicknesses of 5 cm.
True or False?
The waves travel through all three media at different speeds because the media are different.
True
Propagation speed can be correctly recoded with which of the following units? (more than one may be correct).
a. miles per hour
b. mm/msec
c. km/sec
d. inches per year
a. miles per hour
b. mm/msec
c. km/sec
d. inches per year
The propagation speed of continuous wave ultrasound is 1.8 kilometers per second. The wave is then pulsed with a duty factor of 50%. What is the new propagation speed?
a. 0.5 km/sec
b. 0.9 km/sec
c. 1.8 km/sec
d. 3.6 km/sec
e. cannot be determined
c. 1.8 km/sec
What is the best estimate of the distance that sound can travel in soft tissue in one second?
a. one yard
b. one hundred yards
c. one mile
d. ten miles
c. one mile
True or False?
Shorter wavelength sound creates higher quality images with greater detail.
True
True or False?
The wavelength of an acoustic wave is shorter when it is pulsed rather than continuous.
False
The speed of sound traveling through bone is _____ soft tissue.
a. higher than
b. lower than
c. equal to
d. cannot be determined
a. higher than
Compared to soft tissue, the speed of an acoustic wave through lung tissue is _____.
a. faster
b. slower
c. equal
d. cannot be determined
b. slower
What is the best estimate for the speed of sound in tendon?
a. 1,000 m/s
b. 1,540 m/s
c. 1,754 m/s
d. 5,400 m/s
c. 1,754 m/s
As a general rule, which of the following lists media in increasing order of propagation speeds?
a. gas, solid, liquid
b. liquid, solid, gas
c. solid, liquid, gas
d. gas, liquid, solid
d. gas, liquid, solid
What is the speed of sound in air?
a. 1,540 m/s
b. 330 m/s
c. 100 m/s
d. 3,010 m/s
b. 330 m/s
True or False?
Soft tissue is an imaginary construct that actually does not exist.
True
What is the propagation speed of a 5 MHz sound wave in soft tissue?
a. 1,450 m/s
b. 1,540 km/sec
c. 1.54 m/s
d. 1.54 mm/us
d. 1.54 mm/us
If sound travels at exactly 1,540 m/sec in a particular medium, then the medium ____.
a. must be soft tissue
b. may be soft tissue
c. cannot be soft tissue
b. may be soft tissue
If sound doesn’t travel at 1,540 m/sec in a medium, then the medium ____.
a. must be soft tissue
b. may be soft tissue
c. cannot be soft tissue
c. cannot be soft tissue
The propagation speeds of ultrasound waves in muscle, liver, kidney, and blood are ____.
a. exactly the same
b. very similar to each other
c. vastly different
b. very similar to each other
The speed at which a wave travels through a medium is determined by:
a. the sound wave’s properties only
b. the medium’s properties only
c. properties of both wave and medium
d. none of the above
b. the medium’s properties only
What two properties establish sound’s propagation speed in a given medium?
a. elasticity and stiffness
b. stiffness and impedance
c. conductance and density
d. density and stiffness
d. density and stiffness
The characteristics of four media are described below. Which of the media has the slowest propagation speed?
a. high density and high elasticity
b. low density and high stiffness
c. low stiffness and low density
d. low compressibility and low stiffness
a. high density and high elasticity
Compressibility describes a characteristic of a medium. Which two terms describe the same property as compressibility?
a. density and stiffness
b. density and conductance
c. stiffness and elasticity
d. elastane and impedance
c. stiffness and elasticity
When the elasticity of a medium is high, the ___ is high.
a. stiffness
b. propagation speed
c. compressibility
d. reflectivity
c. compressibility
Two sound waves with frequencies of 5 and 3 MHz travel to a depth of 8 cm in a medium and then reflect back to the surface of the body. Which acoustic waves arrives first at the surface of the body?
a. the 5 MHz wave
b. the 3 MHz wave
c. neither
d. cannot be determined
c. neither
