Which component determines the period of an emitted ultrasound wave?

Which component determines the period of an emitted ultrasound wave?

• A. The propagation medium
• B. The transducer
• C. The display unit
• D. The sound source only

Answer: (D)

The period of the emitted ultrasound wave is set by the frequency of the emitted pulse, which is controlled by the sound source (the transmitter/pulser). The period is the reciprocal of that frequency, so the source determines how long one cycle lasts. The transducer mainly converts the electrical signal into sound energy at that set frequency, but it doesn’t change the timing of the pulse itself. The display unit doesn’t affect the emitted pulse at all. The propagation medium only influences how fast the wave travels and, therefore, its wavelength, not the period of the emitted wave. So the period is determined by the sound source alone.

The period of the emitted ultrasound wave is set by the frequency of the emitted pulse, which is controlled by the sound source (the transmitter/pulser). The period is the reciprocal of that frequency, so the source determines how long one cycle lasts. The transducer mainly converts the electrical signal into sound energy at that set frequency, but it doesn’t change the timing of the pulse itself. The display unit doesn’t affect the emitted pulse at all. The propagation medium only influences how fast the wave travels and, therefore, its wavelength, not the period of the emitted wave. So the period is determined by the sound source alone.