Mile per hour (mph)
The mile per hour, symbolized as mph, is an imperial unit that expresses speed in miles traveled per hour. It originated in England, where miles were the standard measure of distance, and gained prominence with the advent of road travel and railways. One mph equals 1.60934 kilometers per hour. The unit remains widely used in the United States, the UK, and a few other countries for road speed limits, automotive specifications, and aviation. Despite global metric adoption, mph persists in daily life and transportation, reflecting historical continuity and practical familiarity in imperial-system countries.
Foot per second (ft/s)
The foot per second, symbol ft/s, is an imperial unit of speed representing how many feet an object travels in one second. It originated in English engineering and physics as a practical unit for measuring velocities on land and in laboratory settings. One ft/s equals 0.3048 meters per second. While less common in everyday applications compared to mph, it is still used in scientific experiments, ballistics, and technical specifications in the United States. The unit bridges imperial measurements with precise, time-based speed calculations.