How Does Sound Speed Affect Pressure Amplitude in Ultrasound?

AI Thread Summary
The discussion centers on calculating the ratio of pressure amplitudes between incident and reflected ultrasound waves at a boundary where the second medium has a 50% higher sound speed than the first, despite both having the same density. Participants express confusion regarding the variables 'c' and 'v' in the pressure equation p = βcv, questioning if they both represent speed or if 'v' signifies something else. There is uncertainty about whether the correct interpretation leads to p = βc² or if a different formula applies. The mention of Fresnel equations suggests a potential avenue for solving the problem, but clarity on the variables is needed. Overall, the thread highlights a need for further explanation on the relationships between sound speed, pressure, and density in ultrasound physics.
Emir Kano
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Homework Statement



Consider an ultrasound beam incident normal to a boundary between two media with the same density, but
where the speed of sound in the second medium is 50 percent larger than that in the first. Calculate the ratio
between the pressure amplitudes of the incident and reflected waves.

Homework Equations



Wave velocity c (ms-1) = wavelength λ (m) x frequency f (Hz)

p = βcv
p = presuure
β = density
c= speed
v= ? (speed as well ?

The Attempt at a Solution



Im confused as to what the c and v are in this case.

I have tried searching and some places are saying its speed squared.

Or have I got the wrong formula and its some derivation.

But I am lost. Is there enough info to answer the question ?
 
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anyone ?
 
no one lol ?
 
Fresnel equations?
 
ideasrule said:
Fresnel equations?

I think Its not that its to do with the p = βcv

But I don't know what the 'c' and 'v' are. In this case do they both stand for speed. In which case the formula becomes p=βc^2. Or is it something completley different.
 

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