So, whether there is a velocity vector given by these velocity vector given above representation a possible fluid flow possible fluid flow. It is a possible fluid flow. So, it can be easily checked it, because again you are using because you have to again say that whether the divergent of q is 0; that means, del u by del x plus del v by del y plus del w by del z whether it is 0. Thus we are now clear about the equation of continuity, it provides us the knowledge about whether there will be a possible motion or not.