Now, if in case of resistance of ships the variables that affect resistance, that influence resistance can be written as, we can list them: first of course, is speed V; size of the body, size of the body can be expressed as a linear dimension L that is, length dimension is L, area dimension is L square and volume dimension is L cube; then, you have density
of fluid in which the body is moving, mass density, rho, which is mass per unit volume; viscosity of the fluid, mu; acceleration due to gravity, we have seen that the wave making resistance is a function of gravity, g; and pressure, we have talked about pressure in some detail of pressure that is, p.