Subject: Compressor Motor: HP v.s. Amps?
From: Bob Engelhardt
Date: 05/10/03 14:47 GMT Daylight Time
Message-id:

Gary Coffman wrote:

On 05 Oct 2003 02:31:09 GMT, a (Dave Baker) wrote:
... However, If we do 10
units of work to the object by moving it in a particular direction and
then
another 10 moving it back again the net work is always 20 units ...

... negative work was done so that net work is
also zero? ...

The problem here is that work is a RATE (of energy).

Work is not a rate of energy. There is no time element in the measure of work.
It is simply force times distance. HP is a rate of doing work.

You can't, or
don't want to, talk about the conservation of a rate (work). The "...
work to the object by moving it ..." is meaningless. You want to talk
about the ENERGY to move the object.

You can talk about either. Work done is a valid measure as is energy consumed
in doing that work. They are not necessarily the same thing though depending on
the efficiency of the process.

I could use 10,000 HP to move it
one direction and .01 HP to move it back.

So it would take longer to move it back than it did to move it there. I'm not
quite sure what your point is.


Dave Baker - Puma Race Engines (www.pumaracing.co.uk)
I'm not at all sure why women like men. We're argumentative, childish,
unsociable and extremely unappealing naked. I'm quite grateful they do though.