30.4k views
5 votes
An ultrasound machine can measure blood flow speeds. Assume the machine emits acoustic energy at a frequency of 2.10 MHz , and the speed of the wave in human tissue is taken to be 1510.0 m/s . What is the beat frequency f beat between the transmitted and reflected waves if blood is flowing in large arteries at 0.0190 m/s directly away from the sound source?

User LukePOLO
by
5.0k points

1 Answer

6 votes

Answer:

The beat frequency is f

f = 52.85 Hz

Step-by-step explanation:

Fe = 2.10 MHz

u = 1510.0 m /s

To find using the flowing in large arteries at 0.0190 m/s to determine the frequency use

v = 0.019 m / s

Δf = 2 * v * f / u

Δf = ( 2 * 0.019m/s * 2.10 MHz ) / 1510m/s

Δf = 52.85 Hz

With precision can find using also

f' = 2.0Mz * (1510 - 0.019) / (1510 + 0.019) = 20.99947 MHz

Δf = |f' - f|

Δf = |2.099947 MHz - 2.1 MHz|

Δf = 52.85 Hz

User Jameo
by
5.2k points