Which engineer first used the term Horsepower?
Horsepower Horsepower Horsepower (hp) is a unit of measurement of power (the rate at which work is done). There are many different standards and types of horsepower. Two common definitions being used today are the mechanical horsepower (or imperial horsepower), which is about 745.7 watts, and the metric horsepower, which is approximately 735.5 watts. The term was adopted in the late 18th century by Scottish engineer James Watt to compare the output of steam engines with the power of draft horses. It was later expanded to include the output power of other types of piston engines, as well as turbines, electric
Tax horsepower tax applying from 1 January 1948. During the early twentieth century, automobiles in the United States were specified with a figure identical to RAC horsepower and computed using the same formula; this was known either as "NACC horsepower" (named for the National Automobile Chamber of Commerce), "ALAM horsepower" (for NACC's predecessor, the Association of Licensed Automobile Manufacturers), or "SAE horsepower" (for the Society of Automotive Engineers). (This last term should not be confused with later horsepower ratings by the SAE.) This value was sometimes used for taxation and license fee purposes. Although tax horsepower was computed on a similar basis