Sound Waves I
Which period value corresponds to an ultrasound frequency of 10 megahertz (MHz)?
0.1 microseconds (μs)
Which period value corresponds to an ultrasound frequency of 2 megahertz (MHz)?
0.5 microseconds (μs)
Which ultrasound frequency corresponds to a period of 0.1 microseconds (μs)?
10 megahertz (MHz)
Which of the following statements best characterizes ultrasound wave propagation?
An ultrasound wave results in vibratory or oscillatory movement of the molecules within the medium through which it is traveling.
Which of the following terms best describes the percentage, or fraction of time, an ultrasound system is transmitting an ultrasound signal?
Duty factor
Which term best describes the number of complete wave cycles that occur in one second?
Frequency
Which of the following choices best describes the effects of sound as it passes through a medium?
It creates pressure peaks and troughs termed compression and rarefaction, respectively.
Which of the following choices best characterizes a Hertz (Hz) frequency unit?
One Hertz (Hz) is equal to one complete pressure cycle per second.
Which of the following choices best characterizes a kilohertz (kHz) frequency unit?
One kilohertz (kHz) is equal to 1,000 complete pressure cycles per second.
Which of the following choices best characterizes a megahertz (MHz) frequency unit?
One megahertz (MHz) is equal to 1,000,000 complete pressure cycles per second.
Which term best describes the duration of one sound wave cycle?
Period
Which choice best characterizes ultrasound wave period?
Period = 1 / Frequency
Which of the following choices best characterizes ultrasound propagation speed?
Propagation speeds are higher through less compressible media and lower through more compressible media.
Which of the following terms best describes the number of ultrasound pulses that are generated in one second?
Pulse repetition frequency (PRF)
Which of the following statements best characterizes ultrasound wave propagation speed?
Sound waves propagate faster in water than through air.
Which of the following choices best characterizes ultrasound wavelength (λ)?
The length of space required to complete one pressure cycle.
Which of the following choices best describes the sound wave frequency?
The number of complete cycles of pressure variation that occur in one second.
Which of the following choices best characterizes ultrasound propagation speed?
The speed at which a wave travels through a medium.
Which of the following choices best characterizes ultrasound transmission?
Ultrasound signals create variations in pressure as they propagate.
Which of the following terms best describes the distance between two adjacent crests of one sound wave cycle?
Wavelength
