Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: CONSERVATION OF ENERGY



Apropos heat and work, thought you might be interested in a little quote
from a sometime professor of physics of some repute - admittedly in
an informal situation, explaining the discovery process for the mass
of the electron (SciAmerican August 97 Commentary/Wonders. P93)

Professor Philip Morrison writes:
"To learn either charge or mass [of the electron] itself, you needed to
know the particle speed. Thomson found that by indisputable means: he
measured the heating of a little metal cup that caught the stream of
[cathode] rays."

That idea for Martian names sounds better and better...

brian

At 20:59 7/21/97 EDT, you wrote:
Questions about "warming":

1) Is it correct to say that two processes by which thermal energy of a
system can be changed (working and heating) are not sufficient and
that a third mechanism (warming) will be very useful?
2) Who was the first to suggest the need the third process and when?
How was this idea received by those researchers whose specialty is
thermodynamics and statistical physics?
3) Is it correct to define the three processes in the following way?
a) heating = temperature-impelled transfer of thermal energy.
b) macroscopic working = force-impelled transfer of internal energy.
c) warming = conversion of macroscopic internal energy (sliding cube
in our situation) into thermal energy.
4) Actually I have another question about warming. Suppose that our cube
is at rest but that an alpha-radioactive material is present inside
of it (alpha particles are not escaping). Should the increase in
thermal energy be called warming? The same question could be asked
referring to internal rusting, for example, due to a large air bubble
inside the cube. Or, more generally, should an internal transformation
of chemical energy into thermal energy be called warming?


If it was up to me I would not use common words, such as heat and work, in
physics. The three physical processes (heating, working, warming), and the
associated there quantities (heat, work, ?) would be expressed by six
distinct words. I have no names for these words but I know what each of
them should stand for. If the Greek and Latin words have already been
exhausted then we can borrow words from other non-living languages.
May I suggest that the following Marsian words are introduced:

Alphing (instead of working), the name of a force-impelled process.
Beting (instead of heating), the name of a temperature-impelled process.
Gamming (instead of warming), the name of the third thermodynamic process.

Alph (instead of amount of work), a quantity in joules (force*distance)
Bet (instead of amount of heat), a quantity in joules (c*m*dT)
Gam (instead of amount of warmth ?), a quantity in joules (???)

What do you think? Do not criticize the names chosen for the words, unless
you have better names to suggest. Focus on the idea of separating loosly
defined words from scientific words which have precise meaning. Loosly
defined words belong to common conversations; science must be done with
words which are not ambigous. How else can confusions and misconceptions
about energy be avoided?
Ludwik Kowalski

P.S. Can somebody compose a list of typical classroom misconceptions
about energy? Here is two of them:

a)'heat and work are forms of energy'
b)'energy is a substance-like quantity'
What else?


brian whatcott <inet@intellisys.net>
Altus OK