Added mass fluid quasi-momentum. Unsteady forces due to a change of the relative velocity of a body submerged in a fluid can be divided into two parts: the virtual mass effect and the Basset force. The origin of the force is that the fluid will gain kinetic energy at the expense of the work done by an accelerating submerged body. It can be shown that the virtual mass force, for a spherical particle submerged in an inviscid, incompressible fluid is where bold symbols denote vectors, formula_2 is the fluid flow velocity, formula_3 is the spherical particle velocity, formula_4 is the mass density
Linear regression linear relationship between the dependent variable and regressors. Thus the model takes the form where denotes the transpose, so that xβ is the inner product between vectors x and β. Often these "n" equations are stacked together and written in matrix notation as where Some remarks on notation and terminology: Example. Consider a situation where a small ball is being tossed up in the air and then we measure its heights of ascent "h" at various moments in time "t". Physics tells us that, ignoring the drag, the relationship can be modeled as where "β" determines the initial velocity of