What distance is horsepower calculated over in the standard definition?

Horsepower is defined based on a specific distance of work performed over time. The standard definition used in the context of mechanical power calculation specifies that one horsepower is equivalent to the ability to perform 550 foot-pounds of work in one second. This means that when calculating horsepower, the distance used is one foot.

Using one foot as the basis for the calculation recognizes the traditional measurements commonly used in the United States, making it a standard reference point in various mechanical and automotive applications. This understanding is critical for anyone learning about engines and performance, as it directly links the measurement of power output to the specific distance involved in the work done.