Starting from the general formula Acc = NetInput + NetP rod, derive the integral and differential forms of the momentum conservation for a system with constant volume. Explain the assumptions under which you get the Navier-Stokes equations. Assume that you do not know the conservation equations for the general quantity; give all the details. Provide the physical meaning and the units of all the terms appearing in the integral and differential equations.

Hint: Acc = Net_Input + Net_Prod --> Acc= (Net inflow by diffusion) + (Net inflow by convection) + (Net production)