Re: Why do we care about heat?

[brian whatcott <inet@INTELLISYS.NET>]

John Mallinckrodt wrote:

> > ... If *you* haul a weight from height H = 1m to H = 2m in the real
> > world *you* have just performed an irreversible process for a number of
> > reasons.
At 07:12 11/1/99 -0500, John Denker replied:

> OK, how irreversible is it?  What percentage of the work *must* be done
> irreversibly?  Can you state a positive lower bound?

Hmmm....where to start?

For my purpose, I will suppose that 'reversible'
implies 100% efficient.

a 2000 Calorie p.d diet (=8.4MJ)
a 120 watt output capability at the 12 hour rate (??)
120 X 12 X 60 X 60 = 5.2MJ

Efficiency = 100 X 5.2/8.4   = 62%


Hehehe...I hope this started your day with a smile.   :-)


brian whatcott <inet@intellisys.net>
Altus OK