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Re: CONSERVATION OF ENERGY, no Q no W + joke



A joke at the end is the reward for still reading my messages.

The phrase "energy = ability to do work" is an invitation to a lot of
trouble. What is an alternative? Would you accept the following initial
formulation?
..........................................................................
Energy is a very abstract concept which can not be defined "in general";
it can only be defined "in particular". After knowing what particular
forms of energy are we will be able to say that "energy" is a generic
word for many particular forms, such as mechanical, electrical, etc.
Mechanical forms of energy include kinetic, gravitational and elastic.
In physics all forms of energy are quatities expressed joules. The word
"total" is often used for a sum of several forms of energy. New forms
of energy are defined by scientists, as needed.
.........................................................................

What about eliminating "work" and "heat" from the arsenal of our conceptual
tools? Is this possible? Is this desirable? How can this be accomplished?

How can the first law be stated without W and Q? We would say that "an
energy change inside a system is always accompanied by an energy change
outside. The two changes are equal in magnitude but not necessarily in
form". Or something else of that kind. The "no in - no out' law of nature,
if you wish.

And what about dS=del(Q)/T? Jim Green reminds is that one subgroup of
changes is producing dS while for the other subgroup dS is always zero.
The Martian words for these two subgroups are alphing and beting. Can
the state function entropy be defined without using these dirty words.

Ludwik Kowalski

A dirty word? This reminds me of a joke, the best I heard this summer.
By the way, the joke ends with a reference to the working conditions of
teachers in a hypothetical school. Yes, there was a dirty four-letter
word in this joke. To minimize the negative impact of that word I will
replace it with a more acceptable word 'sex'. And please do not start
another debate about the meaning of words. You will not believe me but
I really met a Texan whose name was Sexauer, twenty years ago.

A teacher asks a boy about his name and the boy replies, "Sexauer". The
teacher is indignant. "We never use such words". "Yes, I know, but this
is my real name. And I have a sister in fifth grade, you can ask about
her". His teacher went to verify the situation. "Is there a Sexauer in
this class?" "Are you kidding? Sex hour? We dont even have a coffee break."