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Rule
(lemmy.world)
Be sure to follow the rule before you head out.
Rule: You must post before you leave.
Horsepower isn't a measure of how much power one horse can produce at any time, but rather over an entire day. It's roughly the number of horses an engine could replace running 24/7.
Running a horse at 15 horsepower would tire it out rather quickly, so you'd need many teams of horses rotated around to maintain 15 horsepower.