Seeing that a horse is pretty heavy and can move quite quickly how much horsepower does a hosre develop as it must be more then 1hp

A horse develops one horsepower. It can't make more horsepower than one horse - that wouldn't make sense as it would be more than one horsepower and then it wouldn't be a horsepower. Uh?

Seeing that a horse is pretty heavy and can move quite quickly how much horsepower does a hosre develop as it must be more then 1hp

But the heavy ones aren't quick, and the quick ones aren't heavy. James Watt did the original experiments, and while I can believe horses are a bit fitter these days what with growth hormones and so on, the original calibration was against one genuine horse. He harnessed it to a rope, passed the rope over a pulley down into a shaft, tied weights to the end of the rope, and timed how quickly the horse could lift them: 330 foot-pounds per second is what he came up with (i.e. 10lb at 33ft/sec, or 33lb at 10ft/sec). In modern units it's about 750 newton-metres per second, that's to say 750W.

Peter

what about a pony?

what about a pony?

Twenty-five pounds. Obviously.

Peter

Here is a man who amongst many other engineering achievements gave the World a popular and usable unit of measurement.

Oh the irony.

330 foot-pounds per second is what he came up with

I am pretty sure that it was 550 foot-pounds per second, not 330.

Gawd, what kind of a group are that would know this kind of stuff? Stuff like it takes 80 calories per gram to change ice at 0 degrees C to water; and one calorie per gram to raise the temperature of the water one degree; and 540 calories per gram to turn the water at 100 degrees C into steam.

tanstaafl.

I am pretty sure that it was 550 foot-pounds per second, not 330.

Of course you're right, I had threes in my head because it's 33000 foot-pounds per minute. That sounds better.

Peter

Seeing that a horse is pretty heavy and can move quite quickly how much horsepower does a hosre develop as it must be more then 1hp

As Peter described, the "1 hp" measure was based on the ability of the horse to do "external" work (pull something), not on how much power it generated while moving at high speed. A horse can develop much more than 1 HP when moving at high speed, but it can't sustain it for long.

It's all torque anyway.

It's all torque anyway

As the owner of 2 V8's I have to agree

Stuff like it takes 80 calories per gram to change ...

Yeah, but are those calories or Calories?

1 Calorie in calories

Yeah, but are those calories or Calories?


Aaaarrggh! You caught me!

That'll teach me not to try and show off.

tanstaafl.

<nostalgia>

Ah, this brings me back to the days in my materials lab, where we measured energy by using bomb calorimeters, thermocouples and ice...

</nostalgia>

"As you can see from the blue flame, this was a particularly tasty donut..."