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Re: pseudowork

At 9:07 AM -0600 12/21/01, Tom Wayburn wrote:

Please define pseudowork,


Later Tom Wayburn wrote:

The electric current entering your building because the
TV is on is my perfect example of work if the bldg is the Control
Volume.
...
Def. Work is the ability to raise a weight crossing the control volume
surface unaccompanied by entropy (loosely speaking, but good enough for
science :-)

Let's examine the consequences of this definition.

Suppose I bring 10 kg of trinitrotoluene into the aforementioned
Control Volume. Does that act represent 42 megajoules of work?
Certainly it has the ability raise a weight sky-high... but most
people would not call this act "work". Using the word "work" in
such idiosyncratic ways would lead to needless misunderstandings.


The conventional definition of work is the integral of F dot ds.
You can generalize this expression in a thousand ways, but if you
do you are on your own. Please don't call it work, and whatever
you call it you will have to explain what it is and why we should
care. For more on this, see
http://www.monmouth.com/~jsd/physics/thermo-laws.htm#sec-work