Abstract
The result of this paper is the derivation of the expression for the interaction force between two pulsating/oscillating bubbles (the secondary Bjerknes force). This is done by expressing the force using the hydrodynamic Maxwell equations for a fluid. These subsequent equations were written for the quantities: velocity, pressure and density as deviations from steady state. Also, as it will show in the following rows, we found the expressions of the acoustic charge and of the acoustic intensity. Our results may facilitate an approach for the interaction of two vortices and for the interaction of a bubble with a vortex. This approach leads to a model for an acoustic charged particle which has internal angular momentum.