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 motors and other machinery. With the implementation of the EU Directive 80181EEC on 1 January 2010, the use of horsepower in the EU is permitted only as a supplementary unit.
About Horsepower in brief
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 motors and other machinery. The definition of the unit varied among geographical regions. Most countries now use the SI unit watt for measurement of power. With the implementation of the EU Directive 80181EEC on 1 January 2010, the use of horsepower in the EU is permitted only as a supplementary unit. The Jamaican sprinter Usain Bolt produced a maximum of 5 hp 0 89 seconds into his 100-metre dash in 2009. When considering human-powered equipment, a healthy human can produce about 1 hp briefly and sustain about 0.5 hp indefinitely. If torque and rotational power are expressed in coherent SI units, the power is calculated as P{displaystyle tau} P {display style tau } is the power when rotational and torque are calculated in coherentsi units, P is the torque when tau and T is the speed at which the rotational force is applied to a surface is greater than the speed of the vehicle at which it is being driven, and so on. There are many different standards and types of horsepower. Two common definitions used today are the mechanical horsepower, which is about 745. 7 watts, and the metric horsepower, which is approximately 735. 5 watts. In 1993, R. D. Stevenson and R.
Wassersug published correspondence in Nature summarizing measurements and calculations of peak and sustained work rates of a horse. They reported that the peak power over a few seconds has been measured to be as high as 14. 9 hp and also observed that for sustained activity, about 1 hp per horse is consistent with a work rate of about 4 times the basal rate of vertebrates for the 19th and 20th centuries. The unit was created when one of Watt’s first customers, a brewer, specifically demanded an engine that would match a horse, and chose the strongest horse he had. Watt, while aware of the trick, accepted the challenge and built a machine that was actually even stronger than the figure achieved by the brewer. The idea was later used by Watt to help market his improved steam engine. He had previously agreed to take royalties of one third of the savings in coal from the older Newcomen steam engines. This royalty scheme did not work with customers who did not have existing steam engines but used horses instead. Watt determined that a horse could turn a mill wheel 144 times in an hour. The wheel was 12 feet in radius; therefore, the horse travelled 2. 4 × 2π × 12ft in one minute. In 1782, Watt found by experiment in 1782 that a ‘brewery horse’ could produce 32,400 foot-pounds per minute. Watt then judged a horse was 50% more powerful than a pony and thus arrived at the 33,000 ft⋅lbfmin figure.
You want to know more about Horsepower?
This page is based on the article Horsepower published in Wikipedia (as of Nov. 30, 2020) and was automatically summarized using artificial intelligence.
