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The impedance of a soundwave is given by both: $$\frac{\mathcal{P}}{V}=\rho_0c$$ Where $\mathcal{P}$ is the pressure wave, $V$ is the velocity vector of particles, $\rho_0$ is the static value of the gas density and $c$ is the speed of sound\wave. It is very easy for me to understand an impedance in an electrical circuit. The impedance of a capacitor is a measure of how will a capacitor influence the current (flow of electrons through a conductor). In particular, impedance is the negative influence on the current while admittance is a positive influence.

Is there an intuitive explanation with respect to a sound wave? Looking at the $\rho_0c$ term it seems to me that this is a medium-wise constant value. Is that correct? Is there another\better intuition?

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    $\begingroup$ The electrical analogy is that pressure is like voltage (or E-field in an electromagnetic wave) and velocity is like current (or H-field). $\endgroup$
    – Puk
    Jun 15, 2020 at 19:14

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Impedances in circuits are extrinsic while in your questions you are showing the intrinsic acoustic impedance. As you pointed out, it is a material property and intuitively you can say that it shows you how easy it is for a given pressure to obtain a particular particle velocity. I suggest that you check my previous answer on the topic.

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    $\begingroup$ Very helpful. "shows you how easy it is for a given pressure to obtain a particular particle velocity" was what I was missing from your previous answer. Thanks a lot!. $\endgroup$
    – havakok
    Jun 16, 2020 at 15:30

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