1. The problem statement, all variables and given/known data Let R, L, C, K be suitable dimensional constants. In a certain motion of a fluid, the mass density function ρ is given in the Eulerian description by ρ = R*(x1^2+L^2). Is the velocity field v1 = C/(R*(x1^2+L^2)) e1 a possible velocity field? Is v2 = K*exp(-x1/L) e1 a possible velocity field 2. Relevant equations 3. The attempt at a solution I was thinking it had something to do with either the conservation of mass or conservation of linear momentum. Am I on the right track or am I going the wrong way?