Fetal Heart Wall Velocity from Ultrasound Reflection

AI Thread Summary
A sound wave at 2.25 MHz is used to detect the fetal heart wall velocity, with 87 beats per second recorded. The speed of sound in body tissue is established at 1510 m/s. Calculations attempted to derive the heart wall velocity resulted in an incorrect answer of 0.0584 m/s. Participants are seeking clarification on the calculation process and potential errors. The discussion highlights the complexities involved in ultrasound measurements of fetal heart dynamics.
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A sound wave travels at a frequency 2.25 MHz through a pregnant woman's abdomen and is reflected from the fetal heart wall of her unborn baby. The heart wall is moving toward the sound receiver as the heart beats. The reflected sound is then mixed with the transmitted sound, and 87.0 beats per second are detected. The speed of sound in body tissue is 1510 m/s.

I did 87 = x - 2,250,000
F = 2,250,087

so then 2,250,087 = 2,250,000 (1510 + V_heart)/150
which came to .0584 m/s
 
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you divided by 1510 m/s, right?
Did you have a question about this procedure,
or a comment, or are you just bragging? (;>
 
so then 2,250,087 = 2,250,000 (1510 + V_heart)/1510
which came to .0584 m/s


My answer wasn't right =/
 
so then 2,250,087 = 2,250,000 (1510 + V_heart)/1510
which came to .0584 m/s


My answer wasn't right =/
 
anyone else have any ideas?
 

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