One horsepower equals __________ foot-pounds per second.

One horsepower is defined as the equivalent of 550 foot-pounds per second. This unit of measurement comes from the historical context of assessing the power of horses. James Watt, an engineer, originally conceived the term "horsepower" as a way to compare steam engines to the work output of horses.

When we break it down: one foot-pound represents the work done when a force of one pound acts over one foot. Therefore, if an engine or motor produces 550 foot-pounds of work in one second, it is said to have a power output of one horsepower. This relationship is crucial for understanding how power is measured in various engineering applications, particularly in mechanical systems where engines are involved, as it allows for a clear comparison between different power sources.