An average human can peak above 1HP for short amounts of time (think sprinting). They definitely cannot maintain that. I think the Horse Power was defined at a sustainable rate for the horse.
1 HP = 746 watts and most people on a bike would cruise in 100-250 watts range. The top cyclists can maintain more like 400 watts
A horse peaks around 15+ horsepower depending on age and breed they can significantly exceed it. They also generally average above 1HP for long stretches.
1hp is at best one measure of the average consistent power output of an average horse doing a full day of work every day for months. Or about the equivalent of a person doing 0.05 to 0.1 hp.
"Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. He found that, on average, a mine pony could do 22,000 foot-pounds of work in a minute. He then increased that number by 50 percent and pegged the measurement of horsepower at 33,000 foot-pounds of work in one minute."
"A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute"
"his business partner Matthew Boulton standardized the figure at 33,000.
The number wasn't quite scientific: Watt looked for horses at peak performance, and for his purposes, it didn't truly matter how accurate his measurement of a horse's power was as long as it was close enough to be believable. Much like his engine, the metric struck."
Shows several other HP estimates for horses at up to 1.5 HP per hours and even one at 125lb * 3mph over 6 hours = 1 hp. Also includes a peak from a contest at 14.88 HP.
>1hp is at best one measure of the average consistent power output of an average horse doing a full day of work every day for months. Or about the equivalent of a person doing 0.05 to 0.1 hp.
Which is exactly the point. It makes a good unit for figuring out about how much animal an engine replaces.
No, James Watt behaved like a sincere merchant, and he made a more powerful engine than he actually measured, in order to avoid making it again in case he complains that the engine is too underpowered.
Interesting, “It was found that a horse could conveniently raise a weight of 100 pounds attached to the end of the rope while walking at the rate of two and one-half miles per hour, or 220 feet per minute. This is 220 x 100— 22,000 foot-pounds. W att, however, in order to allow for friction in his engine and for good measure added 50 per cent to this amount, thus establishing 33,000 foot-pounds per minute, or 550 foot-pounds per second as the unit of power.” https://lib.dr.iastate.edu/cgi/viewcontent.cgi?article=1466&...
It lists other estimates ranging up to 1.5 HP, and also has peak HP from one contest at 14.88HP though that was published in 1926.
PS: One even has Tredgold 6 hrs. 125 lbs. 3 m. p. h. = 1HP.
Yes, if Watt behaved like today's marketers, he would design his engine to have 25% less power than he measured and sell two engines rather than one. And he would make some screws loose to sell them again and again.
No. 1 horsepower, this instant, equals 746 watts, this instant. An average of 1 horsepower over an hour equals an average of 746 watts over the same hour.
And, a horsepower-hour is a thing. Railroad locomotives are often used by other railroads than the owner (in the US). Those "foreign" uses are often tracked in terms of horsepower-hours.
1 HP = 746 watts and most people on a bike would cruise in 100-250 watts range. The top cyclists can maintain more like 400 watts
https://www.cyclinganalytics.com/blog/2018/06/how-does-your-...