The velocity of a moving body that has attained a constant maximum velocity in which the forces on the body such as those due to gravity are balanced by the resistive drag forces. Particles can be separated from liquids in settling tanks such as lagoons under the influence of gravity. Where the terminal velocity is very slow and a more rapid separation is required, centrifugal separators can sometimes be used where much higher centrifugal forces on the particles increase the terminal velocity and therefore reduce the time for separation. See stokes’s law.