From Bob Clark (93121.1655 EST)
Martin Taylor (931208 18:30) raises the topic of "power" after his
reference to Bob Clark (931208.1410):
ENERGY AND AMPLIFIERS
it is the EMF that is of interest, that does the job.
Martin adds:
And impedance. And that implies power. If the source has
insufficient power, considering the load impedance, the device
cannot have a desired gain.
Where did I suggest otherwise? E = I x R, always, by definition.
(Do you prefer E = I x Z? Same situation.)
But you can't build a system that violates thermodynamic laws.
Nowhere did I suggest that.
As a rule, the higher system needs very little power. But it needs
some. That's why the brain is quite a hot part of the body, isn't
it, and why one can examine the general location of the brain
involved in different kinds of processing by monitoring where the
glucose is used?
Well, of course. What else?
Have I missed your point(s)?
Regards, Bob Clark