Definition: Second per foot (s/ft) is a unit of kinematic viscosity. It represents the time in seconds required for a fluid to flow a distance of one foot under the influence of gravity.

History/origin: The second per foot unit likely arose from practical applications in fields such as hydraulics and fluid dynamics, where measuring flow rates and viscosities was crucial. Its exact origins are difficult to pinpoint but are tied to the development of techniques for quantifying fluid behavior.

Current use: While not as widely used as other viscosity units like centistokes or Pascal-seconds, second per foot may still be encountered in older literature, specific industrial contexts, or specialized applications within engineering and physics related to fluid flow and material characterization.