Note that this satisfies equation 3.15 for incompressible mass conservation. In the former case, incorporation of Einstein's theory of Brownian motion in the analysis of observations of Brownian motion led to a calculation of Boltzman's constant. The electric charge was determined in the famous Millikan oil drop experiment where charged oil droplets were dragged through a fluid by an electric field. It is a surprising fact that a larger portion of all the fresh water of the continental land mass is stored in underground aquifers than in the lakes and rivers on its surface. It also assumes that the pore size is much smaller than the length scale over which and change.
Permeabilities are quite variable.
By considering mass conservation, it can be shown that the term has the same magnitude as and cannot be neglected in equation 6.82 . The stagnation point in figure 6.20 is a point along the stagnation line that is normal to the plane of the figure and runs spanwise along the leading edge of the wing. The term is approximately equal to the ratio of the flow velocity approaching the airfoil to the foil's radius of curvature. This solution is actually a solution to the Navier-Stokes equation because identically in this case.