Archimedes number

English

Etymology

Named after Template:W (c. 287 – c. 212 BC), a Greek mathematician, physicist, engineer, inventor, and astronomer.

Noun

1. Template:Lb A dimensionless number used to determine the motion of fluids due to density differences, defined as the ratio of gravitational forces to viscous forces: $\begin{array}{cc}\mathrm{A}\mathrm{r}& =\frac{g{L}^3\frac{\rho -{\rho }_{\ell }}{{\rho }_{\ell }}}{{\nu }^2}=\frac{g{L}^3{\rho }_{\ell }(\rho -{\rho }_{\ell })}{{\mu }^2}\\ \end{array},$ where $g$ is the local external field, $L$ is the characteristic length of body, $\frac{\rho -{\rho }_{\ell }}{{\rho }_{\ell }}$ is the submerged specific gravity, ${\rho }_{\ell }$ is the density of the fluid, $\rho$ is the density of the body, $\nu =\frac{\mu }{{\rho }_{\ell }}$ is the kinematic viscosity, and $\mu$ is the dynamic viscosity.

Further reading

• Template:Pedia