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Re: Fizzicks Question (even less Audi content)



The Q List Brain Trust kicks in again...

> Hp is something like 33,000 feet /second or something.

** then we start to close in on the units... **

> One horsepower is the ability to lift 770 lb-ft/second.

** or, on another, meeker farm, **

> One horse power is defined as 550 ft-lbs per second.
> That's a purdy good horse.  :-)

Ever been to a horse pull at a rural fair?  Dem horsies is *strong*!

Horsepower:
1.	A unit of power in the U.S. Customary System, equal to 745.7 watts or
33,000 foot-pounds per minute.  [=550 ft-lbs/sec]

[get it? - Watts, named after the guy who invented the steam engine...]

Torque:
1.	The moment of a force; the measure of a force's tendency to produce
torsion and rotation about an axis, equal to the vector product of the
radius vector from the axis of rotation to the point of application of
the force. ... Units of torque include the foot-pound (or pound-foot),
the dyne-centimeter, and the newton-meter.

Sez me, to get ft-lbs from ft-lbs/min and revs/min divide hp by rpms
(ft-lbs/min)/(revs/min)=(ft-lbs/rev) which is as I have been told, in
cars torque is equivalent to hp/rpm - which is why sometimes as hp
increases with rpm, torque can go down.  Peak torque is where the ratio
is highest.  It would also seem to me that this only apples to apples
when the "rev" is similar, ie different for diesels (2-stroke), Wankels,
and steam engines, since the "rev" is not a cancellable quantity between
engine types...

Sorry for the WOB, but whenever (most times) I slept too late for my
physics class, I would go get the notes from Dr. Palmer and conduct my
own class on the lawn (the Science building was sliding into the creek,
it was safer outside).

back to our regularly scheduled programming...
-- 
Huw Powell

http://www.thebook.com/human-speakers

82 (+/-) Audi Coupe