Can someone explain to me the following: I have been told that acoustic impedance is analagous to mechanical impedance. For mechanical impedance (Z), Z = force / velocity and for acoustic impedance (Z), Z = pressure / flow However, in the mechanical case, force refers only to the driving force, whereas in the acoustic case, pressure refers to the net pressure, including effects due to the driving force, restoring force and resistance. So it seems to me that the analogy does not hold. Can anyone add further insight? Thanks.