Earle Horton

Bill, you are right in that this makes apples equal to oranges, because
torque and power do not even describe the same physical quantity. Dave's
5252 rpm is an accident of the units used, and has no physical significance
whatsoever. By proper selection of units or system of measurement, one
could say that "torque is always equal to power at XXX rpm" where XXX is any
number!

If you convert to the SI (International System) and use rotational velocity
instead of rpm, you come up with the relation

W = T * r

where W is power in watts, T is torque in newton-meters, and r is radial
velocity in radians (a dimensionless quantity) per second. Under this
system, the graphs cross when r is equal to 1.

SI units are explained at
http://www.wsdot.wa.gov/reference/metrics/factors.htm

Earle

"L.W. (ßill) ------ III" <----------@***.net> wrote in message
news:440248D7.14442579@***.net...
> Hi Dave,
> I see if I make apples equal oranges, in a graph I've never seen
> before, where I used the same numbers for horsepower as torque they will
> cross close to your numbers:
> http://www.----------.com/temp/3.7LV...rqueChart2.jpg
> God Bless America, Bill O|||||||O
> mailto:--------------------
>
> Dave Milne wrote:
> >
> > Well they won't cross if the engine won't rev to 5252 rpm !!!
> >
> > Dave

Simon Juncal

Earle Horton wrote:
> W = T * r
>
> where W is power in watts, T is torque in newton-meters, and r is radial
> velocity in radians (a dimensionless quantity) per second. Under this
> system, the graphs cross when r is equal to 1.

see kids, I told you higher math was usefull for common everyday life...

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

Simon Juncal

Earle Horton wrote:
> W = T * r
>
> where W is power in watts, T is torque in newton-meters, and r is radial
> velocity in radians (a dimensionless quantity) per second. Under this
> system, the graphs cross when r is equal to 1.

see kids, I told you higher math was usefull for common everyday life...

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

Simon Juncal

Earle Horton wrote:
> W = T * r
>
> where W is power in watts, T is torque in newton-meters, and r is radial
> velocity in radians (a dimensionless quantity) per second. Under this
> system, the graphs cross when r is equal to 1.

see kids, I told you higher math was usefull for common everyday life...

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein

Simon Juncal

Earle Horton wrote:
> W = T * r
>
> where W is power in watts, T is torque in newton-meters, and r is radial
> velocity in radians (a dimensionless quantity) per second. Under this
> system, the graphs cross when r is equal to 1.

see kids, I told you higher math was usefull for common everyday life...

--
Simon
"I may be wrong, but I'm not uncertain." -- Robert A. Heinlein