Horsepower facts for kids
Horsepower (hp) is a unit of measurement of power, or the rate at which work is done, usually in reference to the output of engines or motors. The idea of horsepower was originated by James Watt, who invented the steam engine. Because people used horses to pull carts, it was an amount of energy that could be understood by most people at that time. A human can only maintain about 0.1 horsepower, but an engine can maintain much higher than that. Small motors can create 10 horsepower while a jet engine can create more than 1,000 horsepower.
There are many different standards and types of horsepower. Two common definitions 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.
Most countries now use the SI unit watt for measurement of power. With the implementation of the EU Directive 80/181/EEC on 1 January 2010, the use of horsepower in the EU is permitted only as a supplementary unit.
See also
In Spanish: Caballo de vapor para niños
