| Abstract: | For the model of an elastic dumbbell, i.e., two beads connected by a Hookean spring, the Langevin equations for the beads are formulated. It is taken into account that the friction force contains terms resulting from the inertia of the liquid. The contribution of the dumbbell to the viscosity is calculated from the rate of energy dissipation. When the inertia of the liquid is neglected, the viscosity contribution reduces to Kramers' result and is independent of the mass of the beads. When the inertia terms are added, the result is nearly independent of this mass, but shows a dependence on the density of the liquid. In liquids of low viscosity, the extra term resulting from the inertia may be as large as 25% of the total viscosity contribution. |
